This is how you calculate:
The input+ has a voltage set by the zener diode=Vz. Input- = Input+ due to feedback. So Vsense=Vz. The current through the resistors=Vz/Rsense
This is a good current sink, better than other designs in this thread.
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Low-price resistors, capacitor, and LEDs:
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theasus said:
Could you propose more sensitive circuit ?
I think this is not a sensitive.And this one more sensitive but i couldn't calculate the compenent values(transistor,resistor..)
Could you help about this circuit?And also for this operation we can prefer fet to transistor.But as i said i didn't calculate the right value for one led driving.
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