# Stabilizing a USB +5V (in reality anywhere from 4.5 to 5.5) power source to a true +5V source.

#### Mahonroy

Joined Oct 21, 2014
285
I want to come up with a circuit that is powered from USB that I can use for multiple devices with a microcontroller on-board. Mainly having to do with sensors.
* Analog to digital converters using 5 volt reference.
* Digital to analog converters using 5 volt reference.
* Amplification circuits using multiple op amps that are powered from 5 volts (as well as -5 volts coming from a charge pump), and using 5 volts with a voltage divider to get an accurate amplification.

These are some examples. As you can see, an inaccurate 5 volt reference will lead to inaccurate sensor readings.

#### ErnieM

Joined Apr 24, 2011
8,006
Because for under a buck I get a 1% (or way better for mo \$) fixed voltage that doesn't have glitches from anything else in my circuit and that doesn't vary over line and load variations.

#### marcf

Joined Dec 29, 2014
257