[sdiy] Op Amp LED driver / Current Source problem/solution

[Justin Owen]

Just in case my original post wasn't clear...

This config: http://www.sdiy.org/juz/unipolar_LED.png

works just fine with the required input signal between 0 and +5V.

My concern is a) I was wondering why the LED wouldn't dim completely without that 1M R and b) I've never seen that 1M R added to this config before so I'm worried I've fixed one problem at the risk of creating others (or just done something else dumb).

Thanks,

- Justin