Electronic Circuits and Tutorials
Electronic Schematics - D

Digital Logic Circuits

µC detects transmission rate of RS232 interface -  09/30/99 EDN-Design Ideas.....RS-232 is the most common serial interface in the PC world. Most RS-232 interfaces communicate with the receiver at a fixed transmission rate, such as 9600 baud. But what happens if the transmitter operates with different transmission rates? Different transmission rates..... [Design Idea by Thomas Schmidt, Microchip Technology, Chandler, AZ]

µC forms FM oscillator -  10/28/99 EDN-Design Ideas.....A project required an inexpensive oscillator whose frequency increased step by step from 200 to 400 Hz and then decreased to 200 Hz. The first step was to design a VCO with a staircase driver. However, this approach entailed at least four ICs and many discrete components. An..... [Design Idea by Abel Raynus, Armatron International, Melrose, MA]

µC generates a frequency burst -  02/03/00 EDN-Design Ideas.....Pulse-sonar applications require generating bursts of a given frequency, duration, and repetition rate. Traditionally,  burst generator comprises a crystal oscillator with pulse modulation. But  easiest and cheapest way to generate  bursts is by using an inexpensive 8-bit µC, such as  68HC705KJ1 and 68HC7051A (Motorola]..... [Design Idea by Abel Raynus, Armatron International, Melrose, MA]

µC implements Pushbutton Light Dimmers -  06/18/98 EDN-Design Ideas.....A project required building a synchronous-demodulator circuit to track a line drawn on paper.  beauty of  synchronous-modulator/demodulator approach is its inherent noise rejection.  method rejects ….File contains several circuits, scroll to find this one..... [Design Idea by William Grill, Riverhead Systems, Littleton, CO]

µC makes inexpensive sine-wave generator -  12/17/98 Issue of EDN  You can use A/D converters or external, controllable oscillators to generate sine waves from low-power, low-cost µCs. However, these methods add cost, reduce reliability, increase circuit and software complexity, increase power consumption, and increase overall size. Alternatively.....Page includes several designs.  Scroll to find this one..... [Design Idea by Jorge Luis B Romeu, IdeaWorks LTD, Syracuse, NY]

µC measures High-frequency signals  -  03/02/98 EDN-Design Ideas.....To measure a high-frequency signal using an 8-bit µC, the time period of the measured frequency must be relatively close to the internal clock of the µC. For example, if the internal clock period is 1 �sec, then.…File contains many circuits, please scroll to find this one..... [Design Idea by Stan D'Souza, Microchip Technology Inc, Chandler, AZ]

µC provides analog data to PLC chip -  07/03/97 EDN-Design Ideas.....The low price of programmable-logic controllers (PLCs] makes these small devices a good choice for many system designs. Most of the controllers, however, accommodate only digital inputs. One such.… [Design Idea by Luke Barker, Reinke Mfg Co, Deshler, NE]

µC Provides Wireless Keypad Control -  10/08/98 EDN-Design Ideas.....Portable systems, such as telephone handsets, make extensive use of low-dropout (LDO]regulators. se components provide noise-sensitive parts with a stable power-supply line.....Scroll to find this specific article..... [Design Idea by Lloyd Khuc, Motorola Inc, Austin, TX]

µC reprograms audio DAC via serial interface -  01/07/99 Issue of EDN  You can use a simple µC to continuously program an audio DAC so that it operates in a 20-bit resolution mode ( Figure 1 ]. After power-on,  PCM1710 delta-sigma DAC (Burr-Brown Corp, www.burr-brown.com]operates in its default 16-bit resolution.....Page includes several designs.  Scroll to find this one..... [Design Idea by Lukasz Sliwczynski, University of Mining and Metallurgy, Institute of Electronics, Cracow, Poland]

µC routines clear up errors -  11/10/94 EDN-Design Ideas.....The ZIPfile attached to EDN BBS /DI_SIG #1619 contains executable programs and source code for programs that allow you to program MC68HC11 microcontrollers via an RS-232C connection to your PC. The programs replace obsolete, error-laden programs published in an applications note..... [Design Idea by Mika Maaspuro, Kirstinmaki, Espoo, Finland]

µC squares input signal -  12/19/96 EDN-Design Ideas.....Converting a random-width pulse to a signal with the same frequency but with a 50% duty cycle isn't easy, especially when the specified frequency range is large…. [Design Idea by Yongping Xia, Philips Lighting Electronics Co, Torrance, CA]

µC tool packages focus on specific applications. -  04/01/99 Issue of EDN  Siemens has extended its microcontroller-development tool support with the “Big Box” programme—bundled offerings that provide tool chains from a number of third-party suppliers. The tool set targets a number of “typical” application areas. The company integrates the tools through a standard interface and includes training and support from the tools’ manufacturers. Part of Siemens’ “Space” programme, the Big Box covers 8-, 16-, and 32-bit microcontrollers.....Page includes several designs.  Scroll to find this one..... [Design Idea by Graham Prophet]

µC uses simple tool for angle measurements -  04/10/97 EDN-Design Ideas.....The circuit in Figure 1 uses a 2V, 2250-Hz resolver as an angle sensor. The excitation for the resolver is irregular, using two 90�-phase-shifted, 900-Hz signals. (The stator is the primary winding.] The output signal’s phase changes from 0 to 360� with shaft rotation. The signal amplitude..... [Design Idea by Lev Freidin, Patriot Sensors & Controls Corp, Simi Valley, CA]

µC-based one-shot has wide range -  06/19/97 EDN-Design Ideas.....The µC-based, digitally programmable, monostable multivibrator in Figure 1 has more accurate timing than a conventional RC-based device because a 20-MHz crystal controls the µC. The PIC16C54 is a low-cost, high-speed,..... [Design Idea by Yongping Xia, International Teldata Corp, Los Angeles, CA]

µC Acts as Dedicated Motor-control -  09/11/98 EDN-Design Ideas.....Motion-control systems often use a PWM signal to control the duty cycle for a motor driver or amplifier module.….….Please scroll to find this circuit.… [Design Idea by [Dylan Horvath, Gecko Sysytems Inc, Austin, TX]

µC Based Circuit Performs Frequency Multiplication -  27-May-99 EDN-Design Ideas.....The traditional frequency multiplier requires many elements  a phase comparator to detect the phase error..... [Design Idea by Yongping Xia, Teldata Inc, Los Angeles, CA]

µC controls charge pump as background task -  1-Aug-97 Issue of EDN  Because of power consumption and cost, designers of battery-powered devices mainly choose components that run at 3V or lower. ..... [Design Idea by Carlos Cossio, Santander, Spain]

µC Controls Digital Potentiometer -  10/08/98 EDN-Design Ideas.....Many digitally controlled potentiometers (for example, the LM1971/02/3 from National Semiconductor, www.national.com] incorporate a three-wire serial digital interface, using data, clock, and enable lines....[Design Idea by Lukasz Sliwczynski, University Of Mining And Metallurgy, Krakow, Poland]
