Good evening everyone. I'm Karen McCarty and I'm really delighted to welcome all of you here this evening I know you all braved through this weather, but I promise you this evening's program will reward you for for weathering it, so thank you for coming and Look forward to having all of you participate. I know there'll be a question and answers session at the very end Desenio is a series that highlights the achievements of Latino designers working in the United States Launched in 2014. We are already in our fifth year of programming Desenio has been made possible through the sustaining support of the Latino initiatives pool and the Smithsonian Latino Center Who we are thrilled to share will open their first gallery space in? 2021 the Molina family Latino gallery Dedicated to celebrating the US Latino experience at the Smithsonian's National Museum of American History Tonight's program features Henry Munoz President and CEO of the architecture firm Munoz and Company and Alfonso of Medina architect and founder of T38 studio They will discuss the ways in which urban development can be a catalyst for economic growth and social political equality Focusing on cities within the United States Mexico border border Munoz and Medina will explore how communities can grow responsibly while honoring local histories and traditions Henry Munoz who will speak first Henry Munoz our Munoz the third is a great friend of Cooper Hewitt and the Smithsonian in addition to being on Cooper Hewitt's board He was part of the Smithsonian National Board from 1999 to 2005 and his chairman emeritus of the Smithsonian's Latino Center board as a designer social activist opinion leader Philanthropist and an architect of change Munoz works across multiple multiple platforms that converge at the intersection of politics and the built environment Under the three decades of his leadership Munoz and company has pioneered an approach to architecture and design That acknowledges the rapidly shifting demographics of the United States Munoz and company shapes the skyline and the landscape of the US Mexico borderlands Practicing a community-based architecture and pursuit of a blended cultural expression that more fully reflects our multicultural identity in 2005 Alfonso Medina established Tager 38 focused in real estate development and construction Which since its founding has built over 30 different housing projects and in 2009? He opened T38 studio an architecture design and research office based in New York City and Tijuana He has taught at the University died Ibu Americana in Tijuana Southern California Institute of architecture and a coal super special architecture in Paris in 2013 he was awarded the curbed Young Guns Award and most recently he co-founded MetaLon Group based in New York City a Startup focused on democratizing housing where he currently serves as CEO Following each speakers presentation there will be a moderated discussion with Christina de Leon Cooper Hewitt's associate curator of Latino design Welcome and we will start with Henry Thank You Cara For me the idea of disenyo being celebrated at the Smithsonian Institution is a major Achievement so I want to applaud This museum which I have been a part of and which has been an important part of my life and preparing for this Conversation it became immediately You know I was struck by how important the Cooper Hewitt and how important the Smithsonian Have been to my life and to my career in fact the first time I ever walked into this building I was looking for a slide projector which will show you how long ago that was and it was because the Cooper Hewitt had decided to collect The design archives of Latino designers across the country which was unheard of at the time. I Think it's important for you to understand a little bit about where I came from I'm the little boy in the in the foreground Seated somewhere in the auditorium is the lieutenant the former lieutenant governor of Texas Ben Barnes not long after this I went to work for him This is important because my father was a labor leader along the border between Texas and Mexico and he believed he told me That it didn't matter how small you were you can make a big contribution. He really believed that The movement of a people began with the steps of just one person and he started that thinking within all of his children from a very young age I Thought this was important This is both a drawing and a photograph from later in that day And it was the first time that I remember that people who weren't even born in this country Thought about the American dream didn't believed in the American dream even if they weren't born as Americans So this is my mother That is my little head and this face right here is the face of my brother But I'll never forget that day with these two men who had been working in the fields carrying the American flag and behind them The banner of the Virgen the walla Lupe I think this was the beginning of my political instincts and my belief that Politics is important in developing communities This is my family about the same time and my mother was an incredible designer and Loved fashion and I think if she had been born at a different time She herself would have been a fashion designer and it was really the blending of those two parts of my heritage that Inspired me to become a designer and an activist It My mom told me me who I knew you were gay when you walked out of funny girl singing singing people That's an important part of who I am too and it was the beginning of my understanding of that the country has never been Equal that there are people who are on the outside and people who are on the inside and it was the connectivity to The part of me that is brown connected to the part of me that is LGBT Connected to the feminist part of me when I was very young at the age of 29. I went to work for the last woman governor of The state of Texas who believed that the border between the United States and Mexico was the front door to Opportunity and not the back door to the United States and she tasked me I used to I now have hair like hers, but that is what my used to look like and and she decided that she would change the lives and the condition and the economic development of All of the people along the Texas Mexico border and that taught me an incredible amount about design Years later I went to work for the man that I called the first mestizo president of the United States Because he's not just african-american. He's a mixed heritage and it is that connectivity. I think to people who have Who are empowered by the political system of the United States that really has informed my work over the course of the last 30 years. I Started searching after that experience of working with Anne Richards for an architecture that was unique to my community unique to the border of the United States of Mexico and I found it in the houses of poor people and Didn't find it in universities. I didn't find it in school districts. I found it in places like this and The artist community of the United States The artist community of Texas were the people who took me by the hand and taught me about the kind of scholarly Aspects of of identity of cultural identity and what they were beginning to do This is a very famous piece that was first shown to me by a curator by the name of a malia Malaga mba Called border door and all of that really is important because no no one person No one president of the United States either has the ability to stop what is happening in this country Within a very short period of time This country will be a majority minority and the Latino community of the United States will be leading That conversation and it is a myth to think about us as Immigrants to this country not only because we've been Shaping this country for centuries, but because most of the Latinos who live in the United States We're born in the United States So look at the future of every major American city increasingly Latino increasingly minority Speaking English speaking spanish speaking spanglish and yet none of the schools That I have come into contact none of the urban planning efforts of these great cities of the 21st century are taking into account This massive shift that is occurring in the country In fact over the course of 30 years we began to think about design principles for cities Across the United States that deal with this new American reality Latin America and Latinos were some of the first urban designers in civilization This is a project on the south side of San Antonio that I did in partnership with Ramiro Salazar who was sitting in the front row this evening that brought a public library to a place in San Antonio That was historically rich, but Institutionally poor you can see in the background of this library the 300-plus year-old missions of San Antonio And you also have an opportunity to see the cultural landscape that surrounds those missions that in the 20th century are incredibly rich with Restaurants and retail of people who have who respect the informal beauty of San Antonio that may not be the kind of formalized architecture that we think about but that are incredibly rich and future-looking and This is that library, which is a piece of modernist architecture inspired by the silhouettes and the materials of the mission and Here are examples of that palette of materials and it is Influenced by a series of outdoor spaces that have provided wonderful places for the community to gather And it was for many years the home of the last great drive-in movie theater in San Antonio, Texas And that's the marquee of the mission drive-in and this project really due to the great design talents of My staff at Munoz and company won both a national award from the American Institute of Architects and an American Library Association Award, but most importantly it brought resources to people who needed them Computers and access to books that didn't have them before And it led us to begin working very closely with the National Parks Service on a survey of Latino Historic sites or the lack of Latino influenced historic sites in the country less than 2% of the National Historic Parks National Historic monuments and sites in this country tell the story of women gay people or minorities and this survey of the Latino influence on the country's history Which is very different than the mythology of the founding of the United States Recognized that 400 years ago The United States was founded at the intersection between the Spanish and the indigenous people and That then became this great movement of the National Park Service to declare The San Antonio missions a World Heritage Site all of it connected to each other and When you don't have libraries and you don't aren't in the archives and you don't see yourself in school Telling stories of who you are is incredibly important This is a project that our office did in collaboration with the Cooper Hewitt a Performing Art Center where no performing art centers existed along a stretch of the Texas Mexico border That in the relationship with the Smithsonian Institution was focused on a corrido a corrido is a border folk song that tells the story of people one aspect of people this Project Took shape after a student in a focus group not much larger than this raised his hand after we asked the question What makes Ed couch Elsa? Different from any place else and he said well we play a Football Cody though every Friday before we go out and and get on the field And they said what's that and he said well? It's a piece of music and so the design of the mural on the outside of the building Really mimics the notes of the football Corita, which are called which is called Lamakina Amaria every Friday And so the building looks like this And that's the first drawing of this building which was featured in a major exhibition here at the Cooper Hewitt And it was the first time that anything like that Happened and what was beautiful about that building is that that folkloric dance program of the high school students Became really incredibly vibrant and now More students go to Ivy League schools from Ed couch Elsa independent school district than from any other school district along the Texas, Mexico border and I found in South Texas that we weren't really building institutions that were welcoming or that told the story of who we are that looked like the Students that we were hoping to inspire in fact they were intimidating So this is just one campus that is today known as the University of Texas Rio Grande Valley there was a Planetarium which was the only planetarium along a hundred mile stretch of the Texas Mexico border and it was scheduled to be demolished and instead we saved it and created a science Courtyard surrounded by a 21st century science complex That's the old planetarium which has now been restored and hundreds of middle school students Come to that planetarium and stand in the courtyard and understand that if they stay in school They can become scientists and astronomers, which is the hair at their heritage through the Mayans and the Aztecs and This is the recently completed second phase of that project You can kind of see this mural of the constellations that you now enter through to get to the courtyard And this is the education building which is sitting right next to it which is Educates more bilingual teachers than any other place in the United States. And so we curated words and sayings the choice using Utilizing the talents of those teachers and you can see here That both in English and in Spanish you're on a journey to education. So It is I like to say it's the first bilingual building in the United States. I don't know if that's true enough Because I think that there is a mythology of the way that we were founded as a country, which is not the reality we are a blended culture and It is important to remember that in particular at this moment in our country's history. So this is a building That was a temporary building at Art Basel in Miami built out of 17,000 Mexican soda bottles That was really just intended to talk about the beauty of everyday life In the place that I live and at the end of the exhibition people took the soda bottles But it was an amazing Opportunity to take a piece of the culture of the border bring it to an international art fair and bring attention to the beauty of the way that we live in South Texas and that those explorations became designed in other Way, so we designed a program called Latino victory not just the logo But the idea that we should begin looking at the next generation of Latino elected leadership So that they would be in positions of power to influence these decisions I'm happy to say that this organization that I started with Eva Longoria has elected the first Latina to the United States Senate just elected a Latina governor of New Mexico just elected the first two Latinas ever to serve in Congress from the state of Texas and about 20 more congressmen since then and I think particularly in moments like this having pride is incredibly important when people tell you that you are not Important and that your voice doesn't matter and so Together with Don Graham in Washington DC. I started a scholarship program that today has almost 4,000 scholars for young people who are undocumented in this country and can't get any other form of financial aid and that that is a huge design opportunity and Today I am working with people in this room on a program called Somos Which is a program that is bringing First of all did an assessment of health care or the lack of health care for Latinos in the city of New York and is bringing solutions to that problem and I want to end by talking about Cities and Latino urbanism This is a this is a This is a ditch that won't in the past was the most important thorough way in San Antonio San Antonio is known for its Riverwalk, but back in the 300 years ago the most important outdoor living room was San Pedro Creek, which is connected to the second oldest public park in the United States And because of flooding it became this a ditch and in the last 10 years We've been working on the environmental redevelopment of it turned it into a cultural park have populated it with these incredible murals that tell the story of Texas and the United States It has an affinity with other great places like this around the country This is the Great Wall of Los Angeles, but also Park well in Spain and this mural project in Brazil It is a place that is on a Saturday and a Sunday now filled with people that is this right here is a Rendering of the sky over San Antonio 300 years ago during the founding of the city and we've taken this work and Connected the linear park to the kinds of opportunities that people need to have in order to Excel in their daily lives public transportation access to public education access to Higher education all within a few blocks of this linear park It's funny for me to be standing in a building of the Smithsonian institution Knowing that One day soon there will be a Smithsonian American Latino Museum the gallery of the Molina family is the first step Toward that I was lucky enough to serve as the chairman of the Commission To establish the Smithsonian American Latino Museum, and I believe that some time over the course of the next few years That museum will be created So that people like myself and my husband and the fourth Henry and my family will have an opportunity to understand that their stories are important to the American story that equality really is the guiding principle of our country and That together we have an opportunity no matter what is going on in this country today To make sure that every American feels like their Contributions to this country are respected Well first. Thank you so much for the Invitation. It's an honor to be here at the the Cooper Hewitt sharing a bit about our work on the border San Diego and Tijuana border. I Was actually also born in Texas From my parents moved from Mexico City to Texas was born there Then they moved to San Diego and eventually to do Tijuana where I grew up And growing up in in Tijuana you're like in a different world, I'd say It's not about Tijuana and San Diego. It's not about California and California or Mexico in the States. It's one single region. That's really dependent on on each other and Me growing up for example, we go to the movies in San Diego or When I was 16 I started cycling and I was competing sometimes in the Mexican national Championships and the month after I'd be competing in the US national championships and we would train in In San Diego every day, so I'd go to school in Tijuana would leave school and My best friend and I would cross the border every day go to subway every day I guess it was before keto and gluten and Then go ride our bikes for three hours and come back to to Tijuana So it was never really an understanding that this is a a solid solid border, which I still believe it isn't it's a very porous porous border This is an image that I really love because it really reflects our our practice Our practice is really based on on building It's not about building houses It's about building communities and the way that we're able to really achieve this is through this this amazing people that that are actually the craftsmen that do our our built environment and The reality is that I mean, I'm very naive which could be Something very positive or something very negative But I started my practice when I was 21 had the opportunity to to start a building a house literally and From there really have seen it always as housing as a tool Most of you have probably seen this this image and this is what that border region is like and one of the crazy parts Is what when you're flying to Tijuana? When you're about to land you see the border really clearly and you don't see it because there's a wall But you see it because it's green on one side and it's brown on the other Literally it's kind of crazy saying region same ecosystem, but one side has literally built up to the wall The other one tries to to stay away from it This is literally the border crossing that 12 million people go through a year just walking and another like 50 driving And that is how how protected it's been for a really long time. So I guess in September 2001 But anyways, we still want to build more walls. I guess I guess this is really not enough What's crazy is that people are Doing I don't know an hour or two hours standing in the sun trying to cross and the first thing when you cross is Shopping center. So I guess it's the the American dream So most of our project and most of our work already have we have developed has been in in Tijuana up until right now and I love this phrase by by Machiavelli and I really Always question the idea of nationalism and then dealing with urban Problems and urban scale solutions at a national level, which I think is this insane Regents are so different from each other societies are so different That for me the only scale that you can really work on. I mean obviously first is the single Person and and and how he lives in his own built environment from there you go to To your housemates or your family or whatever then the neighborhood and then the city But I guess that's where it stops. You can't really have plans at a national much less an international level One is a the fourth largest city in Mexico in a quickly quickly growing city Obviously because of its proximity to to San Diego and California one of the biggest economies seen in the world But it started kind of like when I was Vegas before Vegas existed When prohibition happened people would go down to to Tijuana to drink So we actually had some amazing architects from LA do the The horse racetrack do some mansions in Tijuana and and from there that the city kind of evolved So it was always kind of this very informal weird weird thing But it's a city that that expanded without any plans in a very very organic way It was growing about three hectares a day at one point and by 2010 it had like Grown to be One of the biggest city and it's still one of the cities with with the biggest projected growth in in Mexico And this is the the landscape of Tijuana about 50% of the city Has been developed in a very informal way By its own citizens, which I think it's an amazing way to to develop a city if only we could do that here Most of it has been self-built But the thing is that through building like this is the way that you actually do create community For for communities to exist people need to take ownership and pride of where of where they live So if you saw this landscape 20 years before this picture was taken most of that housing was actually cardboard housing But through time and through a lot of people actually working in San Diego and living in Tijuana So they have like good economies. They're actually able to to develop their own houses and they end up being like mansions basically There's also the aspect of RACD that recycles So you can see a lot like a lot of houses that are made up of old Recycled components that come from demolished housing from California a lot of garage door walls recycled windows but in the end there's There's beauty to that and and it's something that has always interested us a lot Doing this this research into there's so many things going on right now in the States related to Affordability in housing and how big of a problem that is But how come in Mexico really sometimes when building like this It has never been a problem people are actually able to customize their homes to whatever needs they have at the moment Multinuclear housing And it's actually a housing that works in a sense It's a a collage city and for me that there's a real beauty in that and in this informality of a city and and An aesthetic richness to that And then you have like the really formal part of it in a city that grown grows in an informal way Then you have this huge super greedy developers that say we're gonna do it. There's the proper way so they do new cities I My master's is in urbanism and and it's one of the words that I hate the most master planning urbanism You can't really masterplan a city Cities need to grow organically So what happens when you actually masterplan a city that in which people living here will take I don't know Two hours to get to work This is a result So whatever has had they start as a really In a really informal way turned out to be very informal communities very formal housing and whatever started in a very formal way And that up being super super informal So a lot of our work has been trying to really understand that that process of how How city making and place making happens This was our first office We started literally there's a piece of land Somebody wants to buy a house you want to do it sure why not Hired some construction workers and literally spent a year building two two houses and just learning basically I Was very lucky to to assemble an amazing team at first this picture was 15 years ago But this guy's are still there Locals there Google. He's like the master in concrete detailing model Tile worker There's still part of the team Jaime is now in charge of actually Larger multi-family projects that we're that we're developing So it is kind of a family that keeps keeps growing and it's kind of like a loop always We're feeding them information and they're feeding us information and everything is informed by by that process and I guess We really wouldn't have been able to to do the work that we've done without this this process Everything is literally a work in progress and what I'm showing you about Tijuana is for us. It's it's one single project so about Three or four years after I started I obviously asked any architect wanted to do something bigger So we found a site and in a different neighborhood than the one we had been working on where you have like this single family mentions Tijuana is a CD that Looks over to San Diego and says this is the most amazing CD in the world California style Mac mansions are beautiful Let's let's replicate them in Tijuana. So most of what you see is this huge huge structures and for us It's completely unsustainable to think that you can have that scale of Housing and in a CD that's growing so much but instead of growing vertically or more densely It's just spreading out. So we bought this site which was sewn for a single family and Really pushed to get permits to do four units instead of one up to the point where where everything was going very slow So we said like It's better to ask for forgiveness than for permission. So we started building and eventually the permits came But I mean, it's the only way that we know of like to really push in an idea I have to really believe in in what you're what you're doing and you can see in scale within the context for families living here take up way less space and most single families around there and I mean, this is why you really learn these guys are way more creative than any any designer or architect Well, there wasn't a ladder available, I guess that could Get them up there in a safe way Then from there we jumped to this project in which we're doing 15 single family houses in one in one single neighborhood This we're all part of that that project this one we invited amazing architect from LA Peter Salander to sign it and we developed and built all of them We had to convince the owner of the land that his idea of doing 10,000 square foot lots that were five hundred thousand dollars each was not really going to to work So he told us well go build your houses and if you can actually build and sell we'll do the streets after So we were so confident that we actually started Developing before there were like any streets or anything We sold the house and the client was super nervous like please tell me there's going to be streets before I moving Obviously in Tijuana you can never be So sure of something like that And in the end every house was different every house was an aesthetic experiment and for us, it's just we have an interest in in doing things and just using very traditional construction methods very affordable materials Just trying to find a different language and trying to do things in in different ways It's interesting because since It's a small team. I Sell I build this house as I know the clients personally you start establishing all of this Relationship with the people that eventually inhabit them So so it's very interesting to really understand how you thought of something He thought oh this work great and then your client is like ah, this is terrible But then now he this guy the client moved to back to Mexico City and we're finishing his house now there because he missed this house in in Tijuana so so much all of them are Within this very kind of suburban context in Tijuana so after this our interest Really shifted into okay, so I guess we've done a couple of single-family houses. We should do more multi-family projects. So we This is the house that Peter from LA designed So we started as an architect wanted to do Larger buildings that could be published in magazines. So We we started working with different developers and since we knew the development Business, it was very interesting because it was a conversation Collaboration in very different ways. So we focused on one single neighborhood and did a couple of projects there This is a 16 unit condo building While that was getting finished here. We got invited to do a competition for a multi-family Building here even larger scale 300,000 square feet of construction. It was super super excited We proposed keeping half of the side as a garden Obviously, we thought that was gonna be crazy and we're gonna lose but it was still worth it and We won and a couple of years after it was it was built and for us It was an amazing experience just to to get to understand how to like business-wise city-wise Construction-wise how you can actually put up a project of this this scale It was an amazing learning experience and for us just having a garden of this scale was the best result We could ask for an amazing view of the city So you can see in context how much the projects relate to to each other And then on to to our ongoing projects as I said, I mean this is our conversation Every day half. No, I'd say most of the time that I'm on my phone and on what's up I'm replying to message messages from construction workers and not so much to from from architects. So for us, it's just about finding different different scales of collaborating with this guys and talking about like, okay, so we found this I don't know if you've heard of and so Mario the auto project Siona project, but we're very interested in and democratization and democratization of high-end design Not only in housing, but in furniture and any scale So there's an ongoing conversation with for example the construction workers of what they think that a chair is or that it should be and Them designing the the furniture that they're actually using to have lunch during their their breaks At construction sites and just different iterations and collaborations. It's kind of like a dialogue. This is This was actually done by the director of the the office here And it was done at the same time that they were doing this So it's this ongoing dialogue that we always have between Tijuana and New York This is a project we're working on right now Just to show how it fits within within the context we went a little bit crazy here the construction workers We didn't like that, but they were able to to pull it off We're very very excited because in the end for us. It's about Tijuana is right now going through this super crazy rapid Densification and there's towers popping all all over the city But for us, it's about showing that there's different ways of doing denser developments Not everything needs to be a tower. It could be horizontal Another project we're doing. This is the house that The same owner from the other White House that we're finishing now in Mexico City for him A project we're doing in in Mexico City in which we're restoring a 100 year old house Putting some additional apartments to it. The house is amazing the state of it Lofts we're doing in Mexico City too And going back to to housing as a tool when we first opened our office here in in New York City One of the first projects we did was this competition in Boston a housing competition ideas competition and my partner and I were like Let's do something crazy What have we learned from from Tijuana and let's do like Tijuana in Boston and we actually won Which was very insane, but but the basic idea was that You have a concrete structure But then most of the modules people would be able to acquire kind of like square footages and then through Self-building they would be able to do their own dwelling space which would be Flexible enough to change through time And really do mixed use in it in a vertical village kind of kind of way So so this project is we're really about adaptability Two years ago we started working in Denver and Denver in this co-living project at the same time we're Working a bit in one in Mexico City. So we thought like now's the time to really think about Architecture not as an aesthetic thing, but what what can we actually achieve through through our buildings? For us it's super important And the focus is always quality of life. That's what we want to offer Anyone that's living in anything that we we have designed. So I guess that most Developers have always this in mind, but for us if you can't do this It's really impossible to offer Dignified housing, which is what our new kind of like Evolution is going to I'm so convicted of that that for the last year this was my house I literally was a nomad just to test out every different possibility of how people live nowadays So I lived in any co-living Airbnb couch Whatever And it was a great great experience to really see The basic needs of people nowadays in a city like like New York to really really understand So we took that Boston project. We pushed really hard and and we made it a reality. So it is it's kind of crazy, but Six years after we actually built that how that Boston project in Tijuana so it's the same idea a concrete structure in which all the walls are are flexible and most spaces are about community It's not about really private space. It's about community. So this is Two or three blocks from the other buildings that we've done in which you could rent an apartment for $2,500 which is kind of crazy for a Tijuana, but that's a market I guess but two blocks away. We did a building in which you could rent a room for $300 So for us, that is what a neighborhood really implies that democratization of housing within one single one single neighborhood You can see how close it is to the other one. There's the other one back here So the basic idea is that it's co-living you have your your bedroom with your own bathroom and share a Kitchen living room with some cameo areas throughout the building. This was actually the second building in the world That's been built ground up specifically for for co-living. So for us It was more of a lab and a place to to test ideas, which we knew was impossible to really test here in New York But I think one of the best things is that really kind of fits within the same way that Self-built architecture has has fit there and then for us that's super important It's not about doing something that stand out stands out because it's super contemporary It's about something that actually blends into its existing context. So I'm gonna go really quickly through Madeleine that's the new startup. We launched which is is focused on Literally just that's a democratization of housing and for us It's going back to this to really understanding what life is and how people live Nowadays and what do we want our our spaces to to offer its inhabitants The world is changing very quickly. I mean eight years ago. There was no over nowhere VMB We lived in a very different way and by 2030 population will be 8.6 billion I'm going from a 50% urban population to a 75% urban population in a world in which Cities are already unaffordable for most young people And if you see how rent has increased compared with income that will only keep getting worse So how can we solve that? A lot of companies a lot of startups are innovating on the software side of it We believe that you really need to to create new hardware in order for that to to happen So we're very focused on how through technology we can change how a building is developed How it's signed how it's built and how it's operated We just moved into very recently to our new office at the full stack factory in the Brooklyn Navy Yards and The ideas that we're testing out how to actually Build prefab in a way that you can make it more affordable than traditional construction because it's crazy But the construction industry hasn't really evolved in 50 years So we're doing different products. One of them is co-living Which is really not new since 88% of millennials in New York already lived with roommates It's just about doing it in a in a bit more formal way And this is our what I would say our innovation is One single prefab module that we can just replicate all over the the world, but in the end This is what a $1400 room would look like and so for us that is dignified housing And that is what most people it's about affordability and quality of life And then we have got the which is another product That's also about housing as a service, but focused a little bit more on the on the higher end aspect of it Just to close off that's basically Tijuana in the context that we're we're working in and and for us bringing that knowledge and that way of doing things in a Mexican and a little bit naive way into Into New York and the work that we're doing here This is the only way that we can really think very differently On the development approach to to housing We've talked to a lot of developers and and everything is just a copy-paste It's a financial model that has been completely solved, but they're never thinking about the the end user So really going back and rethinking the whole model in order to create affordability So that's it. Thank you so much Henry and I'm fun. So for those really incredible and insightful Presentations I I want to leave some time for the audience to ask some questions But I did want to ask you both a question sort of to follow up and maybe press a little bit more some of the ideas that you Brought up in your presentation Henry, I love if you could speak a little bit to this idea that you brought up many times around Latino design and Let you know urbanism. Can you push that a little bit further? Is that something that you think is Very specific to Southern Texas to Texas is that something that can be applied to other areas throughout the United States? I Think it can be applied to any city that has a significant Latino population And that's pretty and pretty much any city in the United States So the interesting thing about that the difficult thing about that is that you know, I'm from a place that is predominantly Mexican and Mexican-American right and we talk about this population of people in the United States as Latino And we're very diverse the way that we relate to our communities our folkloric traditions are incredibly diverse the thing that has a tendency to organize us is Language and so I think it's important to retain what makes you unique and special, but then to build upon it I believe that we're only now as a country beginning to think about the Massive change that is happening in cities all over this country And it's important as you contemplate that massive change to think about the ways in which Latino community can be Relates to its neighborhood right relates to the to the To the informal and the formal culture that you give people an opportunity to design and inform that culture Inform the institutions that are important to that community Across the board not only through architecture, but through the design of institutions public transportation education, etc. So I think Maybe that we have never thought about ourselves Elevated and honored our contributions in a way in which we have sought out the respect of The institutions in our community maybe what I'm really talking about is massive institutional change at this point. So It's only a beginning This is the beginning. I find it really interesting to think about the U.S. Mexican border region and the way those cities are developing in relation to other cities around the U.S. and and how Not only does the landscape Differ, but even just the way the built environment Distrastically differs from a place like San Antonio to New York City and so much of what you showed In your presentation was so rooted in place was so rooted in a Southwest History and identity and so when I when I think about this in a New York City context in Washington Heights context in East Harlem context, it's so Starkly different. There are a lot of similarities and I think The idea around community around place around a shared culture is there but I wonder if if you've thought about those differences and and the way place and landscape really helps form Latinos as as they grow and as they migrate throughout the U.S. Well, I'm just beginning to think about that because I'm working primarily in New York City at the moment with very similar conditions I mean the lack of education the lack of money the the need to develop Community assets is the same the The conditions obviously are incredibly different in New York City than they are in San Antonio, Texas the Communities are different in that they have different folkloric traditions. So what is unique? What is common? I think to these two places Let's just consider the border of the United States of Mexico and Texas and New York City is that it's important for people to Tell you how they view themselves I mean Alfonso showed beautiful Images of the organic nature of people who have been designing for themselves the beginning of my career was really focused on Talking to people who never went to architecture school, right? But who had been responsible for forming their community what I have found in any of any of the places that I work because even In my home state San Antonio is different than Brownsville is different from Laredo Is that it's important for people to tell you how they see themselves and what they need right how they want to build Their future and when you allow people to do that when you give them a sense of ownership even of their schools their institutions Those institutions become more successful right because they can see themselves in it So here in New York what I'm working on right now is not the design of a building first But the design of a reform of a health care system for the city of New York Considering that the majority of the population of New York City Lives in a desert when it comes to health care that these are people who are intimidated by hospitals And how do you then transform that system to relate to the community that needs it? so I Don't know the answer You know years ago my mentor who was the director of culture and creativity at the Rockefeller foundation said you just need To put your head down and on every single project Then you do find one thing that you really want to explore and when you pick your head up in 20 years You're gonna begin to under stay will then begin to understand what that means And so I'm just beginning to understand what is happening in the city of New York But what I absolutely know is the case is that the country needs about a Thousand more Alfonso's and Henry Munoz is and young people to begin exploring the changes that will occur in The cities in the United States. It's going to happen. It's gonna happen Alfonso, I wondered if you can talk a little bit more about Tijuana and the way you've been working on these various developments You know, it's I'm interested in knowing sort of the Economic divisions within some of these neighborhoods that you are building in Do you see? This clear divide. Do you find that it's much more mixed where you have? Working class with middle class with hike, you know with obviously maybe not the top wealthy wealthiest class but This community that you speak about is it? You know, I was just curious to know when you're showing all these images. How mixed is it? I this is something that in New York we struggle with a lot Not creating silos not created, you know, gentrification It's a huge topic within a lot of communities now Not just in New York cities, but in cities across the nation So I wonder if you could talk a bit about what's happening in Tijuana So it's interesting because our practice has really been informed by by experience it's literally learning through through doing and I Grew up in a city that doesn't have a very Mexican identity to it It's a whole other region and it's not just Tijuana. It's Tijuana's and there was one single one single culture and So I never really thought about like I was born in Texas I grew up in Tijuana. I actually had a fake Mexican birth certificate because you couldn't have dual citizenship a while ago Got fixed. Oh well after but There was this this identity in which most of the people I was growing up with were in the same situation So it creates an independent identity that's very unique to to the region and Growing up my dad was was an architect. He would build single-family houses and when he did He built a house in this new neighborhood and and he I guess didn't have money to finish it completely So he built a house we moved in but there weren't any any walls on the garden And this was in a new development that was literally as you seen most images and development in Latin America This wall with the poorest neighborhood right right behind it But we moved in and there was no walls in the garden So every day all the people that would go from this neighborhood go through the back through the wall and go to work They would come down through the the garden literally were having breakfast with a glass window and everybody was walking by And Tijuana was that safe at that moment One point he my dad had bought this vintage Mini Cooper one of those really small ones and you'd see kids carrying it They were like literally taking the car away back to their their neighborhood So for me, it was a very organic thing It wasn't about this fancy upper-class middle-class whatever neighborhood And the understanding is that neighborhoods really need to be mixed in order to be to be alive And things happen organically. It's like the only way that a neighborhood actually actually works But that's the problem with with planning departments because planners here in the States are always kind of have The interest of the developers because you want land value to increase and taxes to increase So if you don't really try to Hack that system you won't be able to change anything and I wonder if you could talk a little bit more about the resourcefulness of Building practices in Mexico and and I think that's something that you see a lot throughout Latin America and other areas of the world where you are using what you have and In in the Southwest there's a term that's often used called Grasquatchismo and is and it's that it's it's using what you have being resourceful and Just doing it And so I wonder if you could speak a bit about how you've used those sorts of Building principles and in some of these projects that you've done in the States where it is very Linear, you know, there's a very specific way of doing things What have what has been some of I think the challenges or or maybe the ways that you have tried to push the boundaries a bit It's been a challenge for sure being used to working in Mexico and now working here Are our way ways of doing things are really different, but again that I guess that naiveness has you can't ask for Pardon after you've started the fact not not in the same way Well, I would think that's what uber and Airbnb have done. I mean if you really want to change things There's really no other no other way and that's why for example, we want to do Housing that's affordable for young people And we could have gone into existing buildings and tried to adapt them or whatever, but the only way is to completely Rethink the the system so we have partners who are developers specialized in in New York And it's been a very interesting conversation because they have there are certain like standards of doing things or finances There are setups and we're like no no we're doing it this way and it's been a very interesting dialogue and I think we have We advance a lot We've been very lucky to have partners for example in a project We're doing in the middle of nowhere in Colorado Who are actually willing to to take risks and and think differently, so It's always a learning curve, I guess but We learn from our construction workers. They were learned from us We learn from our partners here. They learn from us and it's like a loop in my cycle and for I mean in looking at some of these co habit Habitating projects that you're doing. I mean young people Who have jobs who are doing pretty well for themselves? I mean have you thought about how some of these principles can be applied for? affordable housing for You know families that are much lower income and and sort of how some of these design principles can be used for To tackle some of the big problems around homelessness, California being one of the Having one of the highest rates of homelessness Of course definitely in the end you want to have an impact in the largest number of people that that you can and obviously the most affordable Housing is that the more problematic it gets Socially and in every aspect so for us this is kind of like a detonator to to start but but in the end we want to create obviously We see them as housing products because that's what they are and it's a service. There's an evolution to that But for sure, we're really thinking about what a family building would would imply And in the end this is about sharing resources We can't have a sustainable future without really sharing way much more resources than we are right now It's insane in a building in New York City or Brooklyn. There's I don't know five nannies in each floor on a Friday night Why can't you share those those resources? So it's about really rethinking the way people live Obviously there will there will always be an exchange of the size of the the dwelling needs to go smaller in order for Financials to make sense because in the end you're gonna need to finance them through through banks or whatever But you really need to rethink the the whole system in order to have a greater impact on that Yeah homeless Younger families and really affordable housing We're not so much thinking about affordable housing. We're thinking much more about housing that support So I think we're out of time and we're going to open it up to the audience Thank you so much for that dialogue My questions for Alfonso. I was so touched by your image is including the photos of the construction workers and Talking about how you've learned so much from them And I'm curious as to in terms of when you think about the democratize democratization of the design process How much are they involved perhaps in the profit sharing of these projects? So a couple of them that were in the picture have like Participations on on the projects themselves Because they're they're not Employees as we see them. They're partners And they've been partners for 15 years Hi, I just wanted to ask you Could you tell us more about the Fulton project that you're doing in the Brooklyn Navy Yards working over there? So we're our office is in the full-stack factory in the Brooklyn Navy Yards And we're working in collaboration with them to create all the buildings that we're doing prefab within that that factory So the prefab units that you're working on are going to be in that building No, no, no, so any site that we do in in Brooklyn or Harlem The units would be prefabricated there. They're completely finished furniture Everything's put in place in the factory then a crane moves them You could actually move them up by water because the factory is literally on the water And then you just stack them up on the site. So right now it's not a construction method That's actually more affordable, but it takes away a lot of the unknowns Regarding cost time and all the problems that can arise building in New York where it snows or rains a lot of months so We're for us. This is right now about scalability If we want to have that impact then and sold homeless housing the only way to do it is it's to really produce it as a product and Serially produce housing So for us right now This is one step or next step would be to actually set up a factory in Tijuana where we could ship modules to all of California Thank you, Henry and also so my father was an architect in Cuba and a designer in Cuba and then in Miami And so we talk about Latino design, but we know that there are many Latino groups, so how do you how do you view that? How do you see that? How do you integrate, you know Cuban design versus? Mexican and even Mexican, you know, south Texan versus Californian, etc People design for themselves, you know every single project I've ever done from I had a my I think I when I started I thought it was gonna be one thing I was gonna create this mestizo regionalism and Then I found out within a year of beginning the exploration that every single community view themselves differently There were things in common, right? But they were like I said before Laredo was not the same as San Antonio was not the same as Houston was not the same as Dallas and so we developed a process to allow people to design for themselves a Cooper Hewitt was a part of that Conversation right we learned that everybody is a designer if they're taught that their ideas are important and that they have Value and so this the idea behind places that tell stories about people is to allow people To tell you who they are and to try and find a way to express it in the architecture of that building most of my career has been involved in Working very closely with Like I once tried to do a Rascua Chismo project right for the University of Texas system And they thought I was crazy because I showed them pictures of buildings that were organic that were you know Houses of poor people and they go we can't build a university that looks like that And so years later I went to the University of Texas real grand and found that planetarium that they wanted to demolish it said don't demolish it You need to keep it you need to bring young people to it so that they understand that the education is their future that they can be scientists and so Every single community is different and I think the design process needs to respect the Traditions the viewpoint the culture of those people because as you know you know Climate conditions are different Cultural traditions are different and I think that what unites us as Latinos is this incredible vibrancy of Ideas and allowing that to to take place to find its voice. I think it's the most important thing Thank you. Thanks. That was a great talk both. Thank you very much. So there's a planning question for both of you So in New York and in cities big cities in North America. We think in order to animate a street You've got to have retail on both sides of the street in order to keep in order to keep the streets animated almost every City I've been to in South and Latin America Have places like the Malacone Prado the Rambla where you don't have this you you don't have this kind of retail Animation, but you have this extraordinary social interaction that happens on these boulevards and these waterfronts I know that you're the river project you had I mean that made me think about that a lot But do you have you ever have thoughts when you're doing your planning studies of actually Incorporating these sort of older ideas of these Monumental kind of parades where people can actually interact so it seems so common in South and Latin America to me I mean for us, it's it's thinking a little bit about kind of like guerrilla urbanism It's very difficult to plan something like the Ramblas, but we're always thinking about like how can we play small Detonators for that to happen Even if there's no planning permission for it, how can you set up a certain? Certain street level Configuration in which people will actually take over the sidewalk even though it wouldn't be be permitted And we're always kind of trying to To push for that It's amazing here in a lot of neighborhoods in Brooklyn Was in Clinton Hill on Monday how people literally take over the the sidewalk and do barbecues there That's a really vital city and neighborhood and that's what we really need to to push So it's not about the planning scale Or a city scale. It's about developers or architects really putting in small really small Objects and interventions that can make that happen. It's not that complicated I'm not even sure I'm not even sure where retail is going Quite honestly, my husband is significantly younger than me and he never really everything comes to our door Nowadays, right? So I think to build Urban planning practices based on the future of retail is probably not that smart But you're right. Here's where you are right the the great tradition of Planners from Latin America and the Latino community of the United States is based on these Places right these public places like one of the places I absolutely love That taught me so many lessons when I was first beginning this exploration is a theater called the Alameda Right, which was in San Antonio, Texas, which was a theater that was built It was an integrated theater that was built during the time of segregation if your last name was Munoz in San Antonio back Then you had to sit in the colored balcony and this place said no We're gonna integrate people are gonna sit side-by-side in the architectural tradition of the of the theater was the the architecture of the time art deco but rendered through this incredible artistry of the Latino community the Mexican American tradition of craft and It's set on a street that literally was a tree line street the tradition of alamedas throughout Places like Texas and Mexico and Latin America. So I think the idea of Places that are activated by culture right resources the Zones for example what to me I love I mean obviously I love the what they're calling the Latino High Line right the Park that we've been building in San Antonio But I'm just as interested in the way that the opportunity zones but up to them Do you have a do you have an opportunity to be able to walk to a university? Do you have access to health care right? Is there a public school close by what what are the what are the what are the? cultural needs that a community needs that it will always need in order to To access opportunity Hi, thank you very much for this conversation. It's it's enlightening and interesting and Alfonso you you touched a nerve on me before when you were asked a question about affordable housing and you made a distinction between affordable housing and Housing that's affordable and in the context of New York This matters and could you just expand more on that distinction? What is? Housing that's affordable versus affordable housing. I mean for me the understanding of affordable housing is a very political thing Once you go into politics, it's fucked up And you have the result of like a poor door, which is really like it's insane that something like a poor door can happen But again that goes down to planners tax abatements and developers will always find a way to to do that so You're working within systems that are very very established and you have the bankers and the loans and the planners and code and There's so so many components that you have to to go through So if you're thinking of them independently and you're only doing and focusing on one of them your change will be very Very minor and that's why for us We you need to completely rethink all of them in order to do housing That's that's affordable and that's our objective. I mean we see housing as a tool because it's actually a right It's literally everybody should have a decent place to to live So there is that distinction and for us. It's not a political thing. It's just about right Okay, I think we have come up to the end. Thank you, Henry. Thank you Alfonso. Thank you all for being here today


Today we are going through 18th lecture which is continuation of application of signal processing activities of the op amp in terms of negative feedback. We had in the last class let us see discussed the basic signal processing activities like buffer stage, unity gain amplifier, non inverting amplifier design, trans resistance amplifier design, trans conductance amplifier and current control current source design, summing amplifiers and difference amplifiers as an application of the difference amplifier we went for instrumentation amplifier which is the most common amplifier used in instrumentation setups for measuring force, velocity, pressure variation using these bridges, sensor bridges, strain gauge bridges. We have 2 and 3 op amp versions of these instrumentation amplifiers and we had discussed how common mode gain of that topology can be determined based on the tolerance of resistances used in the instrumentation amplifier setup. Under that assumption it is assumed that common mode gain contribution comes mainly from the resistive mismatch in the difference amplifier. It is assumed that the op amp contribution for the common mode gain error is negligible compared to that caused by the resistance mismatch. Differential mode gain evaluation of this and common mode rejection ratio which is nothing but the ratio of the differential mode to common mode gain which is represented as rho. So these are the ones that were discussed and I had given you a problem on 2 op amp instrumentation amplifier evaluation of the differential mode gain and common mode gain. We can apply VB equal to for example minus VD by 2 and VA equal to plus VD by 2 and then what happens is this becomes minus VD by 2 and this becomes plus VD by 2 and this will now have a current which is made up of VD across it okay divided by R dash. So VD by R dash is the current okay and to that this current gets added okay this current is going to be VD by 2R okay. So these two currents will sum up and go through this and establish a potential here which is minus VD by 2 and the drop across this that drop. So that is the voltage at this point okay and the current in this can be then evaluated current this is already known. So this current is then established and this voltage is then obtained as the AD into VD right. So AD into VD this is the differential mode voltage so AD is going to be then obtained as 2 into 1 plus R by R dash that is the differential mode gain okay. Then we can actually apply the common mode voltage to this and then establish what the common mode gain is so if this then becomes VC this also is VC this is VC and this is VC. So now there is no current in this due to the common mode voltage because there is zero potential across this so no current in this. So only these resistances come into picture and it can be established that it depends upon the ratio of these resistances that exactly equal to 1 okay the nominal value as shown here then the common mode gain is zero because of the tolerance of these four resistors it is going to depend upon the tolerance delta and AC can be shown to be equal to 4 delta instead of the 2 delta that we obtained for the 3 instrumentation type we have here this as 4 delta it is therefore slightly disadvantageous to use this for the same common mode differential mode gain this as a poor or CMRR than the 3 op amp version. Obviously this is not a symmetric structure a symmetric structure is always preferred structure of the present day ICs okay and matching is better in these cases and common mode detection is better in a symmetric structure and therefore it is better to use a symmetric structure than an asymmetric structure like this for instrumentation setups okay next effect of finite gain mended product of these op amps are the same as what happens in the earlier feedback amplifier design. So in for example let us take a general sort of summing amplifier topology where we had put these feedback resistors for different voltages to be summed up so we had chosen this as alpha 1 R by alpha n so this is V1 to Vn so if you have such number of resistors put for a variety of number of voltages at the input for summing action then the feedback factor keeps on changing because of this so we have this effect of the gain due to this feedback composite feedback caused by all these resistances so is going to be equal to if this is let us say GB by S open loop gain then the loop gain is GB by S into the attenuation factor of due to all these feedback resistances that is that can be shown to be equal to actually ideal gain which is actually speaking for different voltages we have it as V1 into let us say alpha 1 Vn into alpha n sigma of all these voltages that is the summing action that has taken place with the negative sign that we had already shown. Now what happens due to the finite gain mended product okay of the op amp is that it is S by GB into 1 over the loop gain so GB by S into the attenuation factor is the loop gain so 1 over the loop gain becomes 1 plus alpha 1 plus alpha 2. So the actually the bandwidth decreases by a factor GB divided by 1 plus alpha 1 up to alpha n so this is a reduction of the bandwidth due to all the summing action right. So if you do not want to why did it take place mainly because we have a voltage to current conversion which is not really ideal conversion so the best thing for coupling with a trans resistor amplifier like this is a trans conductor getting different voltages as input and converting directly to current then the gain bandwidth product would have been just the GB. So for a trans conductor the trans resistor amplifier the gain mended product is just 1 by 1 plus S by GB or it is R divided by 1 plus S by GB that is the transfer function. So this method of conversion of voltage to current is not appropriate if you do not want the gain bandwidth the bandwidth of the whole amplifier stage to be reduced because of this. Now let us also consider how an instrumentation amplifier has to be designed based on the transducer that is going to be connected to it. So this is the familiar bridge arrangement for measuring the variation due to resistance occurring because of pressure pressure gauges right strain gauges. So we have balanced condition with this R, R, R and R the common mode voltage will be nothing but VC by 2 these 2 voltages will be the same that will be pretty large in order to have the sensitivity of the bridge large because that directly determines the sensitivity of the bridge. So when delta R change occurs okay in the bridge then we see that the differential mode voltage that is occurring across this is going to be VS into delta R divided by 2 RS plus R. The common mode voltage at this point when it is balanced is going to be VS into R okay divided by 2 RS plus R okay effective change in resistance here is 0 because this changes by delta R negative and this is positive. So effectively change in resistance is 0 and therefore current remains the same okay at all times. So we have this as common mode voltage this as differential mode voltage and an instrumentation amplifier which is not having a perfectly matched structure will have a finite AC non-zero. So that we had seen because of tolerance of resistors used in the instrumentation amplifier. So the output of the instrumentation amplifier is going to be AD into VD which is wanted plus AC into VC which is the error right. So this error has to be minimized so actual value expected is AD into VD that into 1 plus VC divided by rho is nothing but AD by AC which is known as common mode rejection ratio. So it is VC by VD divided by rho that is the error. So that means in normal setups like this VC is very large compared to VD and therefore you must still have rho which is much larger than this VC by VD in order to make this error go to 0 compared to 1. So this is the method of designing okay the instrumentation amplifier for a given bridge arrangement with certain sensitivity factor. Data R by R is what is called as the sensitivity it is dependent upon the sensitivity of the sensor in this case may be a strain gauge okay. So this is what decides the instrumentation amplifier CMRR expected let us say. Now V naught of the instrumentation amplifier is ADVD plus AC VC and this is what is wanted and this is the error component 1 plus VC by VD divided by rho. So now this has to be kept very small let us say if it is expected to be 0.1% okay which is tolerated for the best sensitivity possible for us okay using the bridge then accordingly rho gets fixed. So let us try to solve instrumentation amplifier design problem instrumentation amplifier has to be designed to measure with the specified accuracy and specified change in resistance of the strain gauge. Let the change in resistance be 0.1 ohm that is the level up to which we want measure 0.1 ohm change in 100 ohm okay and the accuracy of measurement should be 1% for the instrumentation we assume that the entire error is due to the common mode rejection ratio. So the 3 op amp configuration is chosen for the instrumentation amplifier as it has superior CMRR okay 3DVMO in comparison with 2 op amp version and it is a symmetrical structure. So let us consider the 3 op amp design now AD is 1 plus 2 R1 okay divided by R dash this R1 okay AC is equal to 2 delta is the tolerance of R1 error is 1 by rho into R by 2 delta R that is what we have established that should be maintained okay better than 1% 1 by 100 delta by R by R is 0.1 ohm in 100 ohm that is the change we would like to measure. So that means 10 to power minus 3. So rho becomes it should be greater than 1 by 2 into 10 to power 5 is 1 by 100 into 1 by 1000 half of that so 97 decibels. So it should be greater than 97 decibels such an instrumentation amplifier you have to design or purchase okay chosen with CMRR better than 97 INA 103 for example costs $5 per unit for 1000 up quantities which has a minimum of 100 decibels which will suit fine as fine right. So R dash to be chosen for that design okay this has all the other resistances already fixed okay R1 for example is 3K that is already there internally we have to connect R dash externally. So R dash is to R1 by AD minus 1 R1 associated with INA 103 is 3K for AD of 1000 therefore R dash is 6 ohm so we have to accurately obtain the 6 ohm and connected at the point which is already pointed out in the IC. The bandwidth of for gain of 1000 is about 80 kilohertz as mentioned in the data sheet. So consider the design of INA given delta and CMRR okay we have to find the AD that is suitable for this for delta we want to build this instrumentation amplifier now okay using let us say op amps instead of going for INA 103 can we therefore build this for our specification with available resistor components that is 0.1% component as far as resistance is concerned tolerance okay of resistor. The op amp is chosen that is TL084 which as a CMRR of 80 dB that means much greater than what is required so we can use that because it is contribution for the error will not be coming into picture minimum AD is equal to 2 delta okay which is 2 into CMRR therefore is equal to 2 into okay delta 1000 into 1000 that is the so this is equal to 2 CMRR is 1000 from 60 dB so 2 delta into CMRR that is the AD required that is 2 so R dash is equal to 2 R1 R1 can be just 1K and then R dash is 2K so this is a instrumentation amplifier that we can design using TL084 okay so what is the consequence of this for a given AD and CMRR what is the delta right. The example 2 is can we therefore design every time such a design is left to us by selecting the proper op amp and the resistors. If AD is given and CMRR is given okay AD equal to let us say 100 okay CMRR is 120 decibels that is 10 power 6 then delta required becomes almost virtually difficult to get not commonly available 0.005% precision component has to be got which is difficult or it be very expensive. So we can as well use the IC which is available as instrumentation amplifier like NEM or 3 hours so let us now consider the trans impedance amplifier design integrator as the basic building block. Now instrumentation is one of the most important front end requirement in current day signal processing activities okay which improves the signal to noise ratio enormously because of here it is differential topology right all common mode signals get rejected because it has it is designed for a very high value of common mode rejection ratio. So the common mode signals like in the case of ECG waveforms etc the most common mode signal most important common mode signal that interferes within the band of the biomedical signal is the 50 hertz component. So common mode rejection ratio ability is an important criteria of the front end of biomedical setups and therefore instrumentation amplifier is a basic unit which improves the signal to noise ratio enormously typical value of common mode voltages which we had already seen in the introduction okay will be of the order of millivolts and the differential mode signal to be amplified is of the order of micro volts and therefore minimum of 1000 common mode rejection ratio okay is commonly expected with most of these instrumentation amplifiers better than 1000 okay. So integrator where is it coming into picture in building block approach integrator is the building block of most of the VLSI analog filters of today. So the building block approach is the most suited approach for VLSI design today and therefore a study of integrator and integration operation is the most of use linear operation okay in signal processing activity. So integrator is nothing but a trans impedance amplifier the capacitor is the integrator the current voltage relationship is voltage okay current through the capacitor is CDB by DT. So if you put a differentiator in the feedback loop of an op amp it should behave as an integrator inverse operation let us look at it. So current through the capacitor is CDV naught by DT voltage across the capacitor CDVC where DT okay and I am putting it in a feedback where this voltage is converted to current okay. So this is a current feedback this current follows this current input current output current follows the input current okay. So this is the current feedback that is occurring at this single node here. So CDV naught by DT is equal to I naught is equal to minus I this is the current fall over here. So V naught is equal to minus 1 over C integral I DT that is all. So V naught by I is equal to minus 1 over CS this is what happens with the integrator this voltage is a virtual ground this is grounded so this virtual ground this current flows through this totally because this is null later no current can be coming through. So this current is equal to minus I naught and that is CDV naught by DT and V naught by I is minus 1 by CS. So please remember that this is a integrator by virtue of the capacitor being put in the feedback path. Now however I can convert voltage to current roughly by because this input impedance is looking like a short circuit voltage is zero current is anything that passes through this okay. So it is acting like a short circuit so this VI if it is applied here always gets converted as VI by R current. So the current in this is VI by R that flows through this and develops a potential okay which is going to be V naught equal to minus okay this is zero so this is the drop 1 by C integral I DT. So this is turning back okay minus 1 by RC integral I DT. So let us look at this gain actually is going to be GB by SA is roughly equal to GB by S. So this itself acts as an integrator so in order to make an integrator okay out of it we are actually utilizing this. So let us see the effect of this finite gain bandwidth product of the op amp on the performance of this integrator of ours. So before that let us simulate this integrator with R equal to 1K and C is equal to 0.1 micro farad the op amp used is 741. Now you will see this is the input waveform that I have applied to this a square waveform okay. So an integration operation should convert it ideally speaking into a triangle. But what has happened is it has done it has done integration but with a lot of error and what is this error due to this is because of the finite DC gain of my which may be very high of the order of 10 to power 5 or 10 to power 6 but because of that okay and it has finite offset voltage offset typically for 741 may be of the order of few millivolts at the input and that offset simply gets amplified by the open loop gain it is DC unstable okay. Now what is integration operation it is 1 by SCR okay ideally. So that means it is DC gain is as much as the open loop gain itself right. So it simply amplifies offset voltages okay by that DC gain N naught and this is the effect of the offset there is no feedback because it is the capacity feedback that is coming into picture there is no DC feedback and therefore the gain is nothing but the open loop gain. So this is the effect of it has almost gone to the saturation you can look at it and it is still working right as an ideal integrator there okay. So next what I have done now is to shunt this capacitor by a large resistance 100 key we have used for R for converting voltage to current 1K and I have now shunted made the capacitor non-ideal by connecting a resistance of 100K across it. Now there is DC negative feedback okay of 1 over 101 okay 1K and 100K form a DC negative feedback of 1 by 101 that means gain for DC is now 101. So the offset effect is only to the extent of gain of 101 or few millivolts 101 into let us say 2 millivolts so 202 millivolts is the offset final offset. So that means it is reduced considerably and you will see that the in the steady state okay is now reproducing only a triangle the effect of offset is considerably reduced okay it is almost not there here visible okay and it is now doing the integration okay. So this slope is determined by 1 by RC right of the integrator that I have used okay R equal to 1K and C equal to 0.1 microfarad is what has been used. So let us see the effect of finite gain might be product of this. So the loop gain of this system if the op amp gain is GB by S this is the op amp gain you are now putting for example in this integrator right you can form the loop this way this is C and this is R. So it is R okay in series with C forming the loop here. So minus GB by S into SCR by SCR plus 1 is the loop gain. So that is what is shown here. So that V naught by VI is nothing but the ideal value 1 by SCR this is the ideal value for the integrator always divided by 1 plus 1 over loop gain this is what we should remember. And loop gain is this if you substitute that we get minus 1 by SCR okay which is the ideal transfer function of the integrator divided by the effect of non-ideality 1 plus 1 plus 1 over SCR into S by GB okay this 1 over loop gain DC loop gain okay 1 over loop gain becomes this. So minus omega naught by S 1 plus omega naught okay if you put omega naught as 1 by CR right then it is 1 plus omega naught by GB plus S by GB okay minus omega naught by S is the ideal value which can be approximated as minus omega naught by S into 1 plus omega naught by GB that is this factor. So that is what is called as the magnitude error this is the magnitude error of the integrator and this is the phase error of the integrator. So that is approximately what changes omega naught of the integrator E as minus omega naught dash and that is modified by the GB it is fixed error and we have a frequency dependent error here which is 1 plus S by GB and it is primarily the what phase error. So it is causing a phase error of S by GB please compare this with what we get in the case of resistive feedback okay here that is capacitor coming into picture in the feedback okay. So in the resistive feedback like summing amplifier or instrumentation amplifier we had already seen that there is only the phase error dominant okay due to the feedback factor okay. So if beta is the feedback factor it is going to become 1 plus beta S by GB right. So and it is going to give only the phase error and the magnitude error is second order and it can be ignored that we had pointed out pretty early okay. Here there is both magnitude error and phase error in the case of integrator. So every integrator contributes to magnitude error because of this omega naught by GB which is fixed and the frequency dependent omega by GB phase error tiny nurse omega by GB which is approximately equal to omega by GB within the bandwidth. So this error becomes important only within the bandwidth for the signal and therefore we have to consider this error every time we encounter an integrator a phase error that means the ideal phase is phase lag of 90 degrees okay which is increased by a factor of omega by GB further lag of omega by GB occurs. Please remember this when we discussed this effect in most of the amplifiers and let us say in filter design later. So now we have an integrator which can be built using a grounded capacitor. So this is what is called as Debo's integrator let us see how this integrators integration this is another alternative integrator. So you can see that VI is the input voltage and this V naught is the output voltage here and we have a feedback okay R and R that means this feedback is V naught by 2. So again the nullator concept this is V naught by 2 this voltage is same as this voltage and there is a positive feedback in order to this is nothing but a low pass filter R and C and that is going to be a non-ideal integrator low pass filter is nothing but a non-ideal integrator okay it can be made ideal by simulating this is V naught by 2 and this is V naught that means the current here flows this way okay and it is going to be a negative resistance that is going to be seen by the capacitor across it. So we can now do the analysis this equation at this point is V naught by 2 into okay the capacitive current SC plus 1 over R plus 1 over R that is the summation of current at this point due to only V naught by 2 this is equal to the current coming in VI by R plus V naught by R. So in this equation if you write now V naught by VI comes out as 2 by SCR okay this gets cancelled with this this gets cancelled with this right and therefore we just get V naught by VI equal to 2 by SCR. So now effect of offset voltage in ahhh an integrator you can see here that the offset voltage in the simulation we have seen already if you do not put a resistance across this so as to cause discharge of this capacitor R okay ahh provide finite DC gain for this DC negative feedback here then most of the input offset gets amplified by the open loop gain of this stage that is A naught typically of the order of 10 to power 5 to 10 to power 6 and the input offset is of the order of few millivolts apart from that if you have this as input stage as bipolar then the base current of that will flow through this okay and ahh so and it causes okay finite offset voltage to appear here because of the finite base current through the source resistance ahh this resistance now this voltage to current converter resistance which may be pretty large okay and then this offset voltage will further cause problems at the output so it will add to this 2 millivolts so in order to compensate for that always ahh resistance is put this we had already talked about earlier also how to reduce the effect of offset current okay this reduces enormously because the same current roughly flows through this also and it causes an opposite voltage to get generated automatically so this is an offset compensation key okay particularly at low frequency ahh omega naught when it is low R will be pretty high and then this offset effect is going to be predominant in such situation this is the way to compensate for the offset in integrators. Now let us discuss differentiator ahh filter design is normally equivalent to solving differential equations or integral equations so you can either use differentiators as basic building blocks or integrators what is wrong with using differentiators. Let us look at the other application of differentiator differentiators if you give ahh sudden change here that sudden change simply gets carried over to this as an impulse okay so these are normally used as time markers for triggering some action okay so these are important components but this active integrator differentiator let us see what it does it is using the concept of converting voltage to current at the input of an op amp with one ahh non inverting terminal grounded so it converts this voltage to current as CDVI by DT I is equal to CDVI by DT so that is the current flowing through the CDVI by DT because it is voltage is zero. So what happens this current is converted to voltage so this op amp is only acting as current to voltage converter or it is a trans resistance amplifier so this CDVI by DT goes through this resistance develops a voltage V naught which is minus IR and that is minus RC into DV naught by DT so V naught over VI becomes minus SCR or it is minus S by omega naught where omega naught is equal to 1 by RC. Amplifies noise because the gain is directly proportional to frequency if the op amp is ideal it is pretty useless as a ahh amplifier amplifies noise okay that ahh white noise which is contained at all high frequencies okay so this is simply dominating and submerging the actual signal in noise. So this is pretty useless okay the more the ideal it is the worse it is for use in any practical circuit that is demonstrated clearly by taking the effect of finite gain bandwidth product. Look gain is again GB by S that of the op amp that of the op amp okay into 1 by 1 plus SCR let us look at it as a loop so RC this is GB by S minus GB by S because this is minus plus okay and this is 1 by 1 plus SCR that is the loop gain. So again V naught over VI is minus SCR which is the ideal value divided by 1 plus 1 over loop gain okay and 1 over loop gain now is this S into 1 plus SCR divided by GB so minus S by omega naught divided by 1 plus S by GB plus S squared by omega naught GB. So now look at the difference the integrator remained a first order in spite of the effect of GB by S so it only cost ahh the lag error of omega by GB to occur here this becomes a second order system this is first order integration and this is low pass filter action so making it basically a loop with second order and we had understood in system design how a second order system behaves. So it can be equated to minus S by omega naught divided by 1 plus S by okay omega naught okay ahh omega n Q plus S squared by omega n squared omega n is the natural frequency of this system which is square root of omega naught into GB and Q by comparison is GB by omega n okay square root of ahh GB by omega naught okay omega n if you substitute this it becomes square root of GB by omega naught. So as normally GB is much greater than omega naught okay the Q of such a system is very very high this causes ringing ringing means we have studied ringing means number of peaks which are countable okay from initial amplitude of unity to one tenth you go. So Q of such a system becomes very high this causes ringing to be sustained before it comes to steady state so it is pretty useless in most of the application. So whenever input changes suddenly okay let us look at the simulation of this we had seen the effect of offset becoming predominant here the ahh triangle is applied what is the expected output is differentiated okay so you should see a square view ideally okay. So differentiation of a triangular view is an ideal square view this way. Now see what happens for R equal to 1 K C equal to 0.1 micro farad okay same value that we had used for ahh an integrator LM 741 okay is the op amp doing it and its gain meant product is let us say roughly 1 mega hertz. So we have ahh huge ringing taking place whenever sudden change okay is expected this is the sudden change that has happened okay and that has got converted into a square wave a sudden change occurring at this point of transition the slope is changing suddenly from this to this okay. So this is the place where the ringing starts again the slope is changing from this to this gain ringing starts right. So now how to design a good analog differentiated in spite of this it is very simple make the queue become equal to 1 that means there will be just one ringing and it will come to study state very quickly. So that is what is done in the next design so R is equal to 1 K C equal to 159 pick of errors and the op amp is still the 741 okay and ahh C has been changed by more than ahh 1000 okay factor from point 1 it has been changed to so that the queue omega naught is 1 over 2 pi R C is made equal to 1 mega hertz Q we have seen is nothing but square root of GB by omega naught GB is 1 mega hertz. So I design my omega naught okay such that the queue of the system is 1. So GB is made same as omega naught and therefore Q is 1 that means it comes quickly to study state and we get back the ideal waveform that we are expecting as an output after differentiating. So this is the way to design systems that take the finite GB gain bandwidth product of the op amp into a con in your design to design better feedback systems okay this way now as an exercise I am making you okay connect an integrator to a differentiator okay having the same value of RC select the value of RC so that the distortion in the waveform at the output is minimal distortion means deviation from what is expected ideally okay by this operation. So square wave is getting converted to triangle and the triangle is further converted to square wave using the same value of RC what is the best value of RC that is to be chosen so that the distortion is minimum that is the problem. So this is having a finite gain bandwidth product effect this also has finite gain bandwidth product effect okay how best to if the op amp is given let us say 741 is what you are used earlier let us say we want to use TL081 instead of 741 okay what is the consequence of this in selection of the components for this you know is what I want you to study and get a relatively distortion free square wave because a square wave okay integrated and differentiated should give back the square wave that I have started with okay if everything is right that means if these parameters are not affecting it should be got perfectly. So how to select okay the gain bandwidth product if RC is given or the other way if RC is okay to be decided how to do that for a given gain bandwidth product for the op amp is what the problem is all about. So I want you to attempt this and show that it is possible to design such a circuit okay with least amount of distortion next we are already seen how a grounded capacitor integrator can be designed okay why can't we do the same thing for differentiated so this is a differentiated design so this is VI and this attenuator gives VI by 2 here so this is VI by 2. So once again let us write the equation at this point VI by 2 into SC plus 1 over R plus 1 over R summation of all admittances here gives the total effect of the current due to this voltage at this node and that should be equal to the current coming gain due to VI at the input and that due to the output okay. So again we have here VI by R and that VI by R gets compensated here by VI by R. So VI by 2 SC equals V naught by R okay so V naught is equal to SCR divided by 2. So I would like you to simulate this okay exercise using similar inputs there and determine the effect of GB by S again it will start ringing how to select the RC so select the same similar RC there also okay so that the Q of this entire design becomes equal to 1 design it for Q equal to 1 for this second order system okay. So this is the exercise that is given to you please try this out and see for yourself how systems can be designed where in the effect of gain bandwidth product can be minimized distortion can be minimized to the extent possible. Now in the next lecture we will be discussing in some summary what we have done in this is to deal with design of instrumentation amplifier specifically 3 op amp version of the instrumentation amplifier which is the most popular one. Some minor modifications to these topologies can be given by actually using transistorized transconductor to feed on to these different amplifiers okay make it work for all gains with the same bandwidth okay as the gain changes the bandwidth is likely to change in the 3 op amp also okay because the feedback keeps changing. So how to counter this by using transconductors as the front end okay. So this is a problem that can be solved in IC design okay and those topologies are already in the market okay with better performance than the 3 op amp version that we had proposed there earlier but that is the basic stage. So in conclusion what we can say is we have just design of other building blocks like integrators and differentiators and the effect of finite gain bandwidth product has been thoroughly understood on how to optimize these designs okay of these integrators and differentiators for a finite gain bandwidth product has been brought out. So in the next class we will be considering how to design a combination of op amp with transistors as transconductors okay in a variety of non-linear applications last signal applications as data compression circuits and data expansion circuits log antilog amplifiers square law and square routing operations using transistors bipolar or MOS.


Constituents of V for North, Fellows and Lucians, greetings. I thank the Holy Spirit for the breath of life, for strength, for family and for constant provision and of course for guidance. It is Christmas time, a time when traditionally we reach out to each other and look out for those in need with greater vigor. It is also a time for reflection and for preparation as we face a new year. Thanks to you, the people of V for North, for electing me as your Parliamentary Representative in what will be for me a memorable election. We promise to put your business first. We started immediately and will continue to do just that. I look forward to working with all of you during this time in government to achieve our goals and to create the reality which kept us awake through our dreams for so many years. As you are aware, we have been dealing with the COVID-19 pandemic as a country, in our healthcare facilities, within our communities and in our families. We have all been affected in some way or another, whether it be in contracting the illness, having family members who did or dealing with the untimely death of our loved ones. Undoubtedly, our mental health was also dealt a massive blow as we were faced with constant restrictions on socializing and physical distancing from our loved ones. Throughout all these difficulties, we stuck together and remained strong. There were some difficult choices for all of us, but we came together as one family, one nation, doctors, nurses, all the staff at our hospitals, fire officers, police officers to slow the spread of COVID-19, at least for now. During this Christmas season, we must all do even more to ensure that we continue to be safe. As we prepare to celebrate, I urge you to remember those among us who need help, the elderly, the vulnerable, children and the challenged. While you reach out to them this Christmas, continue to think of them throughout 2022 and lend a hand as best as you can. COVID-19 has changed the world. Life as we knew it has become even more challenging. However, this is the time when we must get creative, focus and determine to carve out new paths to constant progress. We cannot and must not fold our arms and give up. Our government will be here to help you. I will be there at the table of View for North constituency leaders to lock arms with you to move our communities forward. I also urge all of us in our communities in View for North, those of us from Greece, from Peru and Opecon, from Savans, from Vijaykako, from Belvi, everywhere to be responsible with our actions as we enjoy ourselves. I pray that we will come through this traditional season accident and incident free. Thanks and a peaceful, safe and prosperous new year to all those who have provided support during this COVID-19 pandemic. All of our people in Saint Lucia, both in the public and private sector, the COVID-19 Management Center, governments who are our friends and partners to the leadership and staff of the Ministry of Health, Wellness and Elderly Affairs, the leadership and staff of all of our hospitals and healthcare institutions, particularly our healthcare workers and all those in the frontline of the COVID-19 battle. Thanks to the Prime Minister and cabinet colleagues for their support, both to my constituents and to the ministry which I lead. Happy New Year to the staff at the parliamentary office and their families. May the Holy Spirit bless you and give you peace. I wish everyone an enjoyable and safe Christmas and a happy, happy, healthy and prosperous new year. Blessings to all. Peace and love.