FAN5233

www.fairchildsemi.com FAN5233 System Electronics Regulator for Mobile PCs Features 5.4V to 24V input voltage range Five regulated outputs: 5V @ 5A (PWM) 3.3V @ 5A (PWM) 5V @ 50mA Always On (Linear) 12V/Adjustable @ 120mA Boost (PWM) >96% efficiency Hysteretic mode for light loads PWM mode for normal loads Main regulators switch out of phase 300kHz fixed frequency switching RDS(ON) current sense over-current Reduced BOM; Max. efficiency Optional current sense resistor for precision over-current detect Power Good signal for all voltages Input under-voltage lock-out (UVLO) Thermal shutdown ACPI compliant 24-pin TSSOP Description The FAN5233 is a high efficiency and high precision multiple-output voltage regulator for notebook PC and other similar battery-powered applications. It integrates three pulse-width modulated (PWM) switching regulator controllers and one linear regulator to convert 5.4V-to-24V notebook battery power into the voltage used by the circuitry that surrounds the microprocessor in these systems. The two primary PWM controllers in the FAN5233 use synchronous-mode rectification to provide 3.3V and 5V at over 5A each. They switch out-of-phase to minimize input ripple-current. Utilization of both input and output voltage feedback in a current-mode control allows for fast and stable loop response over a wide range of input and output variations. PWM control in normal operation and hysteretic control under light load provides effici...