Shop OBEX P1 Docs P2 Docs Learn Events
Subject: Power supply question — Parallax Forums

Subject: Power supply question

ArchiverArchiver Posts: 46,084
edited 2000-09-14 22:17 in General Discussion
I have a requirement for the following power supply:

12volt input
5volt output
500ma output current

I have been using the 7805 regulator for this but the heat output due
to the rather high differential voltage (7v) is not acceptable. I need
a more efficient solution which is easy to build and inexpensive. As a
calibration point my 7805 solution uses one regulator and two capacitors
on a 1.5" square PCB.

Hi Victor:

I know of two solutions for you. The first would be to connect a series resistor
(2W size) between the output of the 12V system and the input of the 5V
regulator.

The other thing to do is to heat sink the voltage regulator. There are some clip
on types available; you can also use the screw ons. Also you could attach the
regulator to the inside of the case and use the case as a heatsink.

Lots of possibilities. If you need more information, please let me know.

Gerry Shand, VE6BLI/VE4
Senior Electrical Engineer
gerry_shand@t...

Comments

Sign In or Register to comment.