> >I built his basic SMPS circuit and I'm seeing some behavior
>>that I cannot explain.  It basically works but it is only
>>switching in repetitive bursts. The period of the bursts
>>varies with the size of the output filter capacitor.
>
> This sounds like you have too small a load on it. Increase the 
> current draw
> until it stops chirping, and then see what current draw you have. 
> You may be
> able to get away with a smaller capacitor if you are after really 
> low
> current draw.

Highly likely that this is what's happening. Bigger capacitor allows 
longer period between recharge bursts. But you are welcome to send me 
information off list if you want. My GSR may also be suitable to your 
needs. I intend to write this up properly and put it on  awebpage 
sometime "soon".


        Russell McMahon

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