[time-nuts] SMPS or conventional?

[Bob kb8tq]

Hi

Finding a data sheet on a TEC that goes past *very* basic stuff is essentially 
impossible. The bottom line is that the people who make them very much 
want to sell them to you. Finding information in those data sheets that suggest
problems … not so much. 

The problem is (mainly) physical. The expansion / contraction of the device is 
a big deal. KHz level PWM is (likely) not a problem. Aggressive cycling from
something like a PID is indeed an issue. 

Bob

> On Dec 21, 2020, at 6:43 PM, Hal Murray <hmurray at megapathdsl.net> wrote:
> 
> [Old mail, context is TECs]
> 
> bruce.griffiths at xtra.co.nz said:
>> If the drive current ripple is too high fatigue failure from cyclic
>> thermomechanical stress can be significant. 
> 
> Do good data sheets say anything about that?
> 
> Is there a frequency term in there?  Can I use PWM, which is as much ripple as 
> you can get, as long as the frequency is high enough?  If yes, ballpark of how 
> high?
> 
> Physically, where is the heat/cold generated?  Is it mostly at the junction?
> 
> -- 
> These are my opinions.  I hate spam.
> 
> 
> 
> 
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.