Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Using multiple regulators in a circuit?

Status
Not open for further replies.

Paleoneon

New Member
I'm making a circuit that will need both 12V and 5v rails. Can I put a couple of 7805 regulators in parallel for the 5V rail if I need more than amp or so of regulated 5V current?. The 12V source can supply plenty of current to the7805s.
 
It can be done but isn't recommended as it could be unstable and oscillate.

It's much better to use a series pass transistor, see the datasheet for details.
 
You can use LT1083/1084/1085 regulators, but you can't use ceramic output caps with them.
 
Last edited:
Check this article from EDN.
**broken link removed**
 
Or, you can use multiple 7805s with a small (e.g., 1 ohm) resistor in series between EACH output lead and the 5v bus. That small resistor will allow a small voltage drop between disagreeing regulators and allow them to better share the current at the cost of adding a little "softness" to the supply.

Dean
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top