The FAN5232 is a high efficiency and high precision DC/DC controller for PCs. It has a synchronous switcher whose output can be adjusted from 5V up to 80% of Vin. It also has two linear regulators for standby, 3.3V and 5V. The PWM utilizes both input and output voltage feedback in a current-mode control, allowing for fast and stable loop response over a wide range of input and output variations. Synchronous switching provides best efficiency over a wide range of loads. Current sense based on MOSFET RDS,on gives maximum efficiency, while also permitting use of an optional sense resistor for high precision.