Mega324P running at 5V, wanting to control a subsystem running at 7.5V, upto about 500 mA. I need to control the high side of the subsystem (ground will remain connected). I also need minimal (if any) drain current in the unactivated state - the AVR will be 'sleeping' most of the time, also minimum part count / size would be good.
My understanding is something along this line (number 3) [from ka7ehk / Jim] -
Will work - but I'm needing a bit more handholding / pointers to some application notes / examples for the part numbers / resistor values (or how I can calculate them). I'm looking for the FET equiv of the BC557 / BC546 type 'generic' components. Do I need JFET, MOSFET, IGFET... N or P.... I was originally thinking one P - but now am confused.
I've been digging and struggling to find the key information. I'm sure this isn't an uncommon basic requirement - someone must have writen it up!
Thanks in advance,