General Description

The MAX1980 step-down slave controller is intended for low-voltage, high-current, multiphase DC-DC applications. The MAX1980 slave controller can be combined with any of Maxim’s Quick-PWM™ step-down controllers to form a multiphase DC-DC converter. Existing Quick-PWM controllers, such as the MAX1718, function as the master controller, providing accurate output-voltage regulation, fast transient response, and fault protection features. Synchronized to the master’s low-side gate driver, the MAX1980 includes the Quick-PWM constant on-time controller, gate drivers for a synchronous rectifier, active current balancing, and precision current-limit circuitry.

Features

♦ Quick-PWM Slave Controller

♦ Precise, Active Current Balance (±1.25mV )

♦ Driver Disable Improves Light Load Efficiency

♦ Accurate, Adjustable Current-Limit Threshold

♦ Optimized for Low-Output Voltages (≤ 2V)

♦ 4V to 28V Battery Input Range

♦ Selectable 200kHz/300kHz/550kHz Switching Frequency

♦ Drive Large Synchronous-Rectifier MOSFETs

♦ 525µA (typ) ICC Supply Current

♦ 20µA Standby Supply Current

♦ Compact 20-Pin 5mm ✕ 5mm QFN and Thin QFN Packages

Applications

Notebook Computers

CPU Core Supply

Single-Stage (BATT to VCORE) Converters

Two-Stage (5V to VCORE) Converters

Servers/Desktop Computers