In search of a rail to rail op amp

Discussion in 'General Electronics Chat' started by Turdnugget, May 21, 2014.

  1. Turdnugget

    Thread Starter Member

    Mar 3, 2012
    Hello, I am looking for a good rail to rail input/ output op amp for a project im working on and im open to suggestions.. Also looking for suggestion in some other parts of this circuit.

    I plan on making a 16 Bit R2R resistor ladder DAC which will be 0-5v..
    having 76.29uV increments in voltage.
    I would like to have a op amp that can reach low rail voltage such as maybe 1mV or less..

    I plan on setting this op amp to have a gain of 2 or maybe a lil higher..
    I need to then go from this rail to rail amp into higher power..

    I dont know if I should use a darlington transistor like the tip 120 or not..
    I want to maintain precision but need to amplify the power of the voltage level.. attached is a schematic of the R2R with a op amp..

    The end result i want is a npn being used as a voltage regulator being programmable by the circuit shown

    Thanks in advance
  2. bertus


    Apr 5, 2008
    Turdnugget likes this.
  3. crutschow


    Mar 14, 2008
    What is the maximum signal frequency? What step response do you need?
  4. Turdnugget

    Thread Starter Member

    Mar 3, 2012
    I'm looking to be able to create custom waveforms.. so I think somewhere around 200khz... To be able to move from one analog setting to the next 5uS which would be 200khz