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