peltier element

Forum 2005-2010 (read only) Hardware Interfacing
1

hello

i already connected a peltier element (heating/cooling) with a transistor (on/off) to arduino. now i would like to control the temperature.

the peltier element uses 1.9V and up to 3A. my first thought was using a l293d. but it can't handle 3A (got got itself). my experiments with l298 did not work at all. l298 should handle 3A, it should be able to flip polarity and control the voltage.

do you have any other suggestions for controlling a peltier element?

thanks

michael

2

use an h-bridge with a temperature sensor attached for monitoring

an h-bridge will allow you to turn it either hot or cold (reverse polarity) using 2 pins

Its the same type of component that allows forward and reverse on a motor only no protection diodes are needed since its not an inductive load.

Here is an example for a motor using only 2 pins (I would use a couple more transistors to make sure both couldnt be in the on state at the same time as that would likely cause smoke

http://www.bobblick.com/techref/projects/hbridge/hbridge.html

or a possibly more effecient design using MOSFETS here

http://www.cadvision.com/blanchas/hexfet/np-s.pdf