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Old 04-11-2013, 07:56 AM
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rcheshire (Rowland)
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Join Date: Apr 2010
Location: Geelong
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Linear MOSFET TEC circuit

I'm putting this up here out of interest, in my pursuit of a linear MOSFET driver circuit. This is a copy of a power LED dimmer with a few additional components on the TEC side.

I've been reading about Trench MOSFETs and the capability to run linear. All I have done here is smooth things out - naively, possibly. This works over a range of PWM frequencies. Some component values need adjusting otherwise.

3R resistor is the TEC.

The 5R resistor prevents reverse current in the TEC at start up - 1.67uA is the current through the 2.2nf cap and resistor according to my Android app, Every Circuit.

Not sure of the heatsink requirements yet.

Here it is running at 70% duty cycle, which is typical. The Teensy board PWM output at ~3.75Mhz 0 - 5V.

http://www.candlepowerforums.com/vb/...rent-Regulator
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Last edited by rcheshire; 09-11-2013 at 01:28 AM.
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