General Description

The MAX1816/MAX1994 are dual step-down controllers for notebook computer applications. BUCK1 is a CPU core regulator with dynamically adjustable output, ultrafast transient response, high DC accuracy, and high efficiency. BUCK2 is an adjustable step-down regulator for I/O and memory supplies. Both regulators employ Maxim’s proprietary Quick-PWM™ control architecture. This fast 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. The MAX1816/MAX1994 also have a linear-regulator controller for low-voltage auxiliary power supplies.

Features

♦ Dual Quick-PWM Architecture

♦ ±1 VOUT Accuracy

♦ 5-Bit On-Board D/A Converter

♦ +0.60V to +1.75V Output Adjust Range (MAX1816)

♦ +0.70V to +2.00V Output Adjust Range (MAX1994)

♦ Voltage-Positioning Gain and Offset Control

♦ +2V to +28V Battery Input Range

♦ Differential Remote Sense (BUCK1)

♦ Linear-Regulator Controller

♦ 200/300/550/1000kHz Switching Frequency

♦ 2.2mA (typ) ICC Supply Current

♦ 20µA (max) Shutdown Supply Current

♦ Independent Power-Good Outputs (PGOOD, LINGOOD)

Applications

Mobile CPU Core and Video Processors

Memory I/O and VID Supplies

3- to 4-Cell Li+ Battery to CPU Core Supply

Small Notebook Computers