General Description

The RT8204A PWM controller provides the 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 “instant-on” response to load transients while maintaining a relatively constant switching frequency.

Features

• PWM Controller

► Ultra-High Efficiency

► Resistor Programmable Current Limit by Low Side

► RDS(ON) Sense (Lossless Limit) or Sense Resistor

► (High Accuracy)

► Quick Load Step Response within 100ns

► 1 VOUT Accuracy Over Line and Load

► Adjustable 0.75V to 3.3V Output Range

► 3V to 26V Battery Input Range

► Resistor Programmable Frequency

► Over/Under Voltage Protection

► 2 Steps Current Limit During Soft-Start

► Drives Large Synchronous-Rectifier FETs

► Power Good Indicator

• LDO Controller

► 1.5 Accuracy Over Line and Load

► Adjustabe Output Voltage down to 0.75V

► Independent Enable and Power Good Indicator

► Drive N-MOSFETs within Rail to Rail Controller Voltage

► MLCC and POSCAP Stable

• RoHS Compliant and 100 Lead (Pb)-Free

Applications

• Notebook Computers

• CPU Core Supply

• Chipset/RAM Supply as Low as 0.75V