General Description

The MAX1630–MAX1635 are buck-topology, step-down, switch-mode, power-supply controllers that generate

logic-supply voltages in battery-powered systems. These high-performance, dual/triple-output devices include on

board power-up sequencing, power-good signaling with delay, digital soft-start, secondary winding control, low

dropout circuitry, internal frequency-compensation net works, and automatic bootstrapping.

Features

♦96% Efficiency

♦+4.2V to +30V Input Range

♦2.5V to 5.5V Dual Adjustable Outputs

♦Selectable 3.3V and 5V Fixed or Adjustable Outputs (Dual Mode™)

♦12V Linear Regulator

♦Adjustable Secondary Feedback

(MAX1631/MAX1634)

♦5V/50mA Linear Regulator Output

♦Precision 2.5V Reference Output

♦Programmable Power-Up Sequencing

♦Power-Good (RESET) Output

♦Output Overvoltage Protection

(MAX1630/MAX1631/MAX1632)

♦Output Undervoltage Shutdown

(MAX1630/MAX1631/MAX1632)

♦200kHz/300kHz Low-Noise, Fixed-Frequency Operation

♦Low-Dropout, 99% Duty-Factor Operation

♦2.5mW Typical Quiescent Power (+12V input, both SMPSs on)

♦4μA Typical Shutdown Current

♦28-Pin SSOP Package

Applications

Notebook and Subnotebook Computers

PDAs and Mobile Communicators

Desktop CPU Local DC-DC Converters