I'm trying to use Webench to design an inverting buck boost power supply with the LM25574. Input 8-14V, Output -9V @ 100 mA, Fsw 700 kHz. Webench gives me a design that is topologically correct. But many of the component values seem questionable. For example, the values given for Cramp and Rramp are about twice what one would think from the datasheet discussion (for a non-inverting design). The value for Css doesn't make any sense. The datasheet does not give a design procedure for an inverting configuration, so I have no way of verifying what Webench is doing. My main concern is getting the compensation components correct.... How can I proceed with this?
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