The McP1601 is a synchronous Buck (step-down) switching regulator that can continuously supply 500mA of load current. This Dc/Dc converter can provide output voltages of 0.9V to Vin with an operating efficiency that can exceed 92%. Althoug 500 mA Synchronous BUcK Regulator From old datasheet system
Replaced by TPS40075 : Midrange Input Synchronous Buck controller With Voltage Feed-Forward 20-QFN -40 to 85 Mid Range Input Synchronous Buck controller with Advanced Sequencing and Output Margining 24-VQFN -40 to 85 3-TERMINAL 0.1A NEGATIVE VOLTAGE REGULATORS 三端0.1A负电压调节器