Embedded newbie

One day I needed a simple R-2R ladder DAC, and needed an output buffer for it, so I started to design one. Initially I was planning to use the LM358, but then I remembered seeing an op amp from TI that would be more suited for the job. First off, I'd like to clear up two things for those that might wonder. Why I need an output buffer? For example the R-2R ladder digital-to-analog converter circuit cannot drive anything by itself. You should be able to observe the waveform with an oscilloscope (typically 1 megaohm input impedance) but probably cannot even drive a sound card input (~10kohm) with only the ladder. You need a buffer amplifier that has a voltage gain of 1 and can drive a low input impedance.   Why linearity is so important? So you get the value you wanted out from the circuit without any distortion. The TLV2472 single-supply op amp makes a great buffer. Unlike with the LM358 , the output is linear from 0 to VDD so you don't have to have an extra voltag...

I was in a need of an analog output output for my Arduino, and I found quite many different digital-to-analog converter (DAC) solutions by googling around. So finally I decided to gather them on one page as a reminder for myself and a guide for others. So here it comes! R-2R ladder DAC The most common way to build a DAC is to use a R-2R ladder circuit. Make: Online has a photo-guide for building one. However, this DAC has no output buffer, which would make this circuit a bit more reliable and working with all kinds of loads. MAKE: Online's DAC shield Make: Online - Proto-DAC shield for Arduino A Direct digital synthesizer build using a R-2R ladder DAC - This is worth a look if you're interested in outputting audio. R-2R ladder DAC with output buffer For the best results, you should use an output buffer in the DAC. The buffer separates your R-2R ladder from the load you connect it to and makes the result non load dependent. Here's maybe the best tutorial I...