Properly Sizing MOSFETs for PWM Controllers - Fundamentals of Properly Sizing MOSFETs for Synchronous Buck Controllers and Their Effects on Efficiency

Application circuit for SP6133 is a synchronous buck (step-down) PWM controller and is designed to drive a pair of external, n-channel, enhancement mode MOSFETs at a fixed 300 kHz frequency. The part is designed for single supply operation at input voltages ranging from 5V up to 24V and can generate output voltages as low as 0.8V and up to 95% of the input voltage. The part powerful internal MOSFET gate drivers can drive the gates of external MOSFETs capable of handling output currents as high 30A