RT8228B - Richtek

RT8228B Single Synchronous Buck PWM Controller

The RT8228B PWM controller provides high efficiency, excellent transient response, and high DC output accuracy needed for stepping down high voltage batteries to generate low voltage CPU core, I/O, and chipset RAM supplies in notebook computers. The constant on-time PWM control scheme handles wide input/output voltage ratios with ease and provides 100ns “ins.

Features

z Built in 1% 0.5V Reference Voltage z Adjustable 0.5V to 3.3V Output Range z Support Pure MLCC Output Capacitor z Quick Load Step Response within 100ns z 4700ppm/°C Programmable Current Limit by Low Side RDS(ON) Sensing z 4.5V to 26V Battery Input Range z Resistor Programmable Frequency z Internal Ramp Current Limit Soft-Start Control z Drives Large Synchronous Rectifier FETs z Integrated Boost Switch z Over/Under Voltage Protection z Thermal Shutdown z Power Good Indicator z RoHS Compliant and Halogen Free Applications z Notebook Computers z CPU Core Supply z Chipset/RAM Supply as Low as 0.5.