Variable Power Supply

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Using the PI Expert to design a power supply.
Probably using a TOP261 or TOP262
The requirement is for a variable power supply from 18 to 32 volts.
Is there a better tool than PI Expert to design the power supply ?
Is there a way to input the parameters for a variable supply into PI Expert ?
Or, is is possible to design it at a fixed voltage, change the output reference
resistors and see how the power supply reacts ?

Dear Vgoeckner.

PIExpert and PIXLs are the best and only tools to desing power supply with Power Integration controllers.
TOP-Switch in PIExpert & PIXLs does not support analysis of multiple output voltages delivered to one secondary winding.
To replicate what you want to achive you could do the following; desing you power supply for the "main" output voltage and current (maybe heighest power?) ,then, keeping your transformer parameters (NS,NP), device size, output and input capacitance constat you can modify your output voltage to the new value. Now you need to match the inductance value obtained in the first desing. You can do that by using KP as handle. You need to increase KP value if you want decrease your inductance and vice versa. At this point you should be be able to analyze how the same power supply behaves with the new output conditions

Just a reminder, when you change your output votlage and keep NS constant, you'll need to modify your VOR to match the number of primary Turns NP

InnoSwitch3 CP and PRO in PI Expert have this feature built in with the new Design Evaluation Tab. Your outputs voltage specification though are too high for InnoSwitch3 whose output voltage range goes from ~4V to 21V.

Hope this may help
Let us know if you have further questions.
We will be glad to help

Best regards
PI - Star Lord