TEC current settings help (DDL driver)

So, I'm building a TEC labby, and I'm planning to use a 12V 3A wall adapter (unregulated), connected to a fan (for the TEC) and a 7809 regulator (to get a 9V output). The output of this regulator will be connected to two DDL drivers, one plugged to a TEC at 600mA (the TEC is rated 10V at 1A), and the other one set to 190mA (for a 6X ASFW diode; it will also have a 50 ohm pot at the input to change the output of the diode in real time. Yes, this works; I have a labby with this setup).

First question : will this work?

Also, I made some tests with a TEC module (fan, heatsink, and TEC). I tried, using a 12V 500mA, unregulated wall adapter, to set the TEC at 400mA, but I only reached 303mA, and with a 7812 regulator, 298mA. What surprised me most is that I got the exact same results with a 9V battery and with both DDL drivers...

Anybody can explain this and help me?

:bumpit:



Any help.....

I can tell you that you don't need anywhere near full current or voltage in the TEC to cool a laser diode, so as long as the TEC is cool I wouldn't worry. Just assemble the system and set the TEC at a decent temp within the spec for the diode. 20-25C works very well.

The TEC is slightly cool to the touch, I would say it's reaching 10°C.

Is this good enough?

As long it doesnt put too much stress on the diode it should be good at that temp.

Just keep in mind that at 10°C, condensation might start forming on the lens or inside the diode itself. I'd say 20°C or so would be better.

Ok, but I have a quite large heatsink so it should help stabilizing the temperature aroud 20 (ambient).