AVR-Chat

Roy wrote:
> See attached WORD file of the Switcher CAD III plot of the circuit below.

Thanks Roy for the analysis info.

> *From:*  *Russell Shaw

Thanks Russell for the original circuit.

One problem of course is getting enough current to drive the LEDs to a 
reasonable brightness. This is mostly due to having them run from what 
is effectively a 2.5 Volt rail. Differences in brightness between red 
and green LEDs because of different operating voltages is also 
exacerbated.

I'm leaning towards using a shift register like the 74HC595 and 
sending it data via the SPI - in my current design this allows me to 
control up to 8 LEDs with just the original extra pin!  And it takes 
about the same PCB real estate too.

Peter






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