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Electronics => Electronics => Topic started by: Private Reid on June 20, 2008, 08:00:41 PM

Title: 5V Linear Regulator
Post by: Private Reid on June 20, 2008, 08:00:41 PM
Enerywhere i go to buy a regulator, the person serving me askes if i would like it to be a negative or positive regulator?!

is there a difference?

which one should i buy?

5v negitive

5v positive
Title: Re: 5V Linear Regulator
Post by: ALZ on June 21, 2008, 12:46:01 AM
Hi Private Reid:  Yes there is a difference. Not to be a smart ass but I don't know what you are builting so I don't which one you need. What it means is if your ground is negative and the other power rail is positive then that's a  positive  regulator. If your ground is  positive and the other power rail negative then it's negative regulator.
Title: Re: 5V Linear Regulator
Post by: Afroman on June 21, 2008, 12:27:28 PM
The vast majority of the time you want a positive 5V regulator.
For example, going from a 9.6V battery pack down to 5V to power a microcontroller will require a positive 5V regulator, such as the classic LM7805.

Negative regulators are generally only used for creating regulated negative rails for use with certain amplifier circuits.