increasing output cap on SMPS

Thunderchild said:

the chip will auto compensate and reduce frequency as neccesary

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You are talking about LT1074? LT1074 is fixed frequency switcher - it compensates by changing duty cycle.

I think at very low outputs it switches over from continuos to discontinuos at a lower frequency

The frequency shifting is to help detect output short conditions at low power. It does not make up for the inductor being of the wrong inductance. You are going to decrease the capability of the supply if you go with a larger inductance.

The guy at picbits might be using it that way, but it's not optimal. The inductor is specifically selected using the switching frequency and inductor current needs. Nothing else affects it.

I could see where you might need a larger current carrying inductor, but it should be the same inductance.

EDIT: Finally see what you're seeing on the datasheet. Let me calc the value for your exact specs and post it tomorrow. Stupid internet is down at the house. (

smanches said:

The guy at picbits might be using it that way, but it's not optimal.

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picbits is a member of this forum actually, I don't know the reasoning behind the larger inductor I'm just doing as told