0
votes
1answer
120 views

Common VCC and multiple grounds

I need to plug a micro controller in device which seems to run a PSU with a common VCC and two "grounds" A common 0V a -3.3V and a -5V. I want to add a 3.3V powered microcontroler (The easy part) and ...
3
votes
4answers
1k views

How to supply a negative voltage from a simple battery or psu?

I am using an op amp (741). I need to supply its pin 4 with -5 volts using a power supply unit from a computer or from a simple battery. How am I going to do that?