Current source OP1177


I would like to use OP1177 for a current source, in data sheet of OP1177 is an example of values ​​Rs and Cs to get stable. I would like to know how have calculated these values, someone can me explain how this affects the stability and control loop ?

Thank you

  • Hi Sisamyo, 

    The load capacitance works with the output impedance of the amplifier and introduces a pole into the operational amplifier's transfer function. Please see the application note at this link to read more about it. 

    For the Rs and Cs for stability, the numbers on page 16 of the datasheet should give you a rough estimate of what values you might need to use. Beyond that, we recommend that you verify your chosen components on bench in order to check whether you can get a stable response. 

    I hope this helps.