Hi,
I'm looking at an existing circuit trying to understand how it is built to further my electronics knowledge. There is a part of the circuit thats puzzling me though.
The circuit has a 6502 microprocessor on board. One of the standard I/O ports on the micro is connected to the Base of a BC212 transistor via a 10K resistor. The collector of the BC212 is connected to the supply rail (+12v) and the emitter is connected back to the Microprocessor's VREF pin for the onboard A/D converter.
Do you think this is so the supply to the VREF can be controlled by the Micro ? To conserve power maybe ? (The circuit is battery powered).
Cheers, Tim.