Guys,
I have a couple of questions that may seem silly but I’ll go ahead and ask them anyway for my own enlightenment. Here goes:
- Why not use a precision voltage reference instead of a voltage divider hung off Vcc to derive Vref?
We could do that I guess, but the reference doesn't need to be precise since the current is dialed in. It is a regulated supply so it should be stable.
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Why not ditch the x10 amplifier that generates a guesstimate of the output current reading and replace it with a summing amp that gives the actual current reading regardless of how many FETs are working?
That's a good idea, but Jeremy's about just putting in a real ammeter is the best. Then it doesn't matter how many FETs or what value sense resistor we use.
**broken link removed**