General Description

The MAX1717 step-down controller is intended for core CPU DC-DC converters in notebook computers. It features a dynamically adjustable output, ultra-fast transient response, high DC accuracy, and high efficiency needed for leading-edge CPU core power supplies. Maxim’s proprietary Quick-PWM™ quick-response, 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

♦ Quick-PWM Architecture

♦ ±1 VOUT Accuracy Over Line and Load

♦ 5-Bit On-Board DAC with Input Mux

♦ Precision-Adjustable VOUT Slew Control

♦ 0.925V to 2V Output Adjust Range

♦ Supports Voltage-Positioned Applications

♦ 2V to 28V Battery Input Range

♦ Requires a Separate +5V Bias Supply

♦ 200/300/550/1000kHz Switching Frequency

♦ Over/Undervoltage Protection

♦ Drives Large Synchronous-Rectifier FETs

♦ 700µA (typ) ICC Supply Current

♦ 2µA (typ) Shutdown Supply Current

♦ 2V ±1 Reference Output

♦ VGATE Transition-Complete Indicator

♦ Small 24-Pin QSOP Package

Applications

Notebook Computers with SpeedStep™ or Other Dynamically Adjustable Processors

2-Cell to 4-Cell Li+ Battery to CPU Core Supply Converters

5V to CPU Core Supply Converters