modified 6 years ago

Version 2

unlisted

This vision doesn't used diodes. Instead, it uses a second BJT to take care of maintaining the right base voltage for the main BJT. This circuit works fine here, but on the breadboard (with the same 2n2222a) didn't maintain a constant current. There was a 5% increase in current on closing the switch. It's not as weird as the version 1, but still, I can't figure out why a constant current wasn't maintained.

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