How-to: Add a DAC (digital to analog convertor) to your Pi
MCP4725 12-Bit DAC with Raspberry Pi
Add a DAC (digital to analog convertor) to your Raspberry Pi
We have a new tutorial - Already mastered Analog Inputs with the Pi, and looking for a new challenge? How about: How can I generate an analog output on the Pi?!
There are several ways you can accomplish this, but one of the easiest and most flexible is to use a dedicated IC called a Digital to Analog Convertor (or DAC). A DAC allows you to specify a numeric value (0..255 for an 8-bit DAC, 0..4095 for a 12-bit DAC, etc.), and the IC will output a voltage based on the supply voltage, and relative to that numeric value. For example, using a 12-bit DAC like the MCP4725 we'll be using here, setting the value to 2048 on a 3.3V system will results in ~1.65V output on the DAC.
This guide will show you everything you need to know to be able to generate precise analog outputs using your Pi and the MCP4725 12-Bit I2C DAC, from connecting everything up, to how to use our easy Python library.
http://learn.adafruit.com/mcp4725-12-bi ... spberry-pi