MP9931GR-Z

MP9931GR-Z is an MPS high-voltage synchronous buck controller in a QFN-23 4 x 4 mm package, listed in the Active Part Numbers table on the MPS product page (a -P variant is also listed there). It drives a pair of external N-channel MOSFETs rather than integrating the power stage, so output current is set by the external switches and inductor, not by the controller itself. The product page specifies an input range of 7 V to 100 V, switching frequency up to 1 MHz, 0.45 mA typical quiescent current, a nominal 0.88 V feedback reference and 99% maximum duty cycle. The selection point is the 100 V input window in a 4 x 4 mm footprint: auxiliary and housekeeping rails fed from 48 V buses or rectified industrial supplies can be generated locally, instead of adding a separate isolated supply for a low-power rail. Selection advice: quote the -Z code exactly as listed on the MPS product page, and treat the published 0.88 V feedback value as the nominal design target - the full electrical-characteristics table sits in the MPS datasheet, so designs that need guaranteed feedback limits should pull the datasheet values before layout freeze rather than designing to a tolerance that has not been published here. Parameters verified against the MPS MP9931 product page (Active Part Numbers and headline specifications).