On 20/04/2011 03:26, V G wrote:
> Or should I do active control with a microcontroller? I can have the
> microcontroller read the output of the opamp and control the Darlington p=
air
> through a DAC.

You could, but I think that would be overkill for a simple constant=20
current load. Unless you want to make it programmable for different=20
tests, like pulsing the current, or ramping up/down at different rates.
If not, you have everything you need with the opamp. At the very least,=20
it's probably best to understand the simple version before adding=20
complexity.

--=20
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