Whoa! did I step in it, or what!
A big thank you to Georg Hager and Thomas McGahee who
pointed out that you don't need a series resistor if you have a
feedback emittor resistor. They both mailed me privately, but
I think it is usefull info for most PIClisters, so here it is :
{Quote hidden}> _ Positive
> |
> |
> _|_
> \ / IR LED Imax=4.3/Re
> V
> ---
> |
> |
> |
> |
> |/c
> PIC-------------------| NPN
> |\e
> |
> |
> / Re
> \ 47 ohm Re=4.3/Imax
> /
> \
> /
> |
> |
> -----
> ---
> -
The base current 'sees' a series resistor of Tgain*Re anyway,so adding a series resistor is bit sit
silly, really. I can't beleive
I stepped into *that* one!
Thanks, guys.
--
Friendly Regards
Tjaart van der Walt
spam_OUTtjaartTakeThisOuT
wasp.co.za
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