i don't have a way to analyze circuit efficiency other than a variable power supply that shows voltage and amps.
i also don't want to trust the calculations provided by the chip maker. i want to verify results.
it's easier for me just to change inductors and test with power supply.
i am taking into account inductor resistance by selecting different uH values with very close to same resistance.
1. if i select the inductor value that gives set amp draw at lowest supply voltage, is that the highest efficiency?
2. will higher value caps decrease required supply voltage?
thanks

i changed from a 100uH, 600mohm inductor to a 47uH, 200mohm.
required supply voltage to operate at desired current went down 0.5volt.
the difference in resistance is 400mohm x .4a = .16volt.
where did the other voltage savings come from?
thanks

anybody?

 

The best efficiency occurs for the lowest input volts times amps for a given output.