Electronic – 5v always from +5V and GND

power supplyvoltage

Thinking about supply voltages, and just voltages in general used to power anything, does, say a 5v supply alway have to come from +5V and ground, or can you bias it to any other set 5V apart, like 12V and 7V, or 2V and -3V?. Since voltage is just potential difference right?

Now I know they bias transistors for amplifiers, but could you do such a thing to a microcontroller? (No application just really curious).

Best Answer

You most certainly can.

But, be sure to take care to shift all your datasheet values correctly. This especially includes absolute maximum ratings. Also have a look at the protection diodes often found around IC pins.

What makes this often very useless (or sometimes very useful) is that the logic levels are also shifted.

This is in particular done with operational amplifiers. There the manufacturer may even be nice enough to specify typical shifted supplies for you.