I'm designing a TEC circuit using an FET H-bridge and PWM controller. I'm basing my design on a TI Application Note that uses the IC UC3638, a PWM DC motor controller, to drive the TEC, using a thermistor circuit to supply the control voltage.
Datasheet: http://www.ti.com/lit/ds/symlink/uc3638.pdf
Application Note: http://www.ti.com.cn/cn/lit/an/slua202a/slua202a.pdf

The UC3638 seems perfect for driving a TEC in this configuration since it has a current sense input, error amplifier, and a seperate high and low output that trigger when the input is above a certain threshold, and when the input is below a different threshold, thus preventing both sides of the H-bridge to be "on" at the same time.

The issue is that the UC3638 is pretty expensive (8 bucks a pop) and no one seems to keep very much stock. I think it's a relatively old chip.

Does anyone know of a decent PWM H-bridge controller that could be used for this purpose? I like the idea of using a DC motor controller, since the circuits work basically the same way, but I don't want to get stuck using UC3638 for the above reasons.

Thanks

 

Hello,

I found this thread "moderated" (taken out of sight).
This sometimes happens with new members using links.
I have approved the thread and made it visible to others.

Bertus

 

Thank you. I had posted it earlier and noticed it didn't appear on the forum even after several hours so I decided to rewrite it and post it again. I appreciate the help.