I am trying to provide a pulsed voltage (square wave) to a resistor that stays at 4V for a few ms, then steps up to 5V for a few ms, then back down to 4V and so on. The square wave signal is provided through a DAQ card but the card does not have the required current capacity. So I am planning to use an op amp that can source a max current of at least 120 mA and use it in unity voltage gain configuration to source the voltage from the DAQ card and the current from the power supply.
What would be the best op amp that I can use for this application keeping power supply requirements and output current in mind? I am not an electronics engineer, so some of the parameters on the datasheets are confusing.