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Modifying a DC-DC boost circuit Answered

I'm building a circuit that would run off roughly 7v and convert it to 12v using the LM2577 (LINK). the datasheet (LINK) provides an example circuit that will output 12v @ 800mA. I need a little more power than that. around 1.25 A. my question is that if the 100mH inductor was replaced with a larger one. say a 150mH one, would that increase the current output? i would also replace the 680uF cap with a bigger one to reduce ripple. FYI the LM2577 is rated to convert 3.5v-40v to 12v.

any information or direction would be appreciated

picture is from the national semiconductor datasheet page 3


If you read the pdf, there's a section "application hints", which gives a simple formula for calculating your maximum load current. For 7V in, it gives 1.225A.
Note this is a voltage regulator, current is load-dependent up to the device limitations.


Its never as simple as just changing something like component. Everything has knock on effects. Go to National's website for the 2577, and select tools/ webench, and run their design wizard, with the parameters you have - minimum AND maximum input voltage, output voltage and current, and see what the makers recommend - I suspect it isn;t the 2577.