DESCRIPTION

The LTC?3888/LTC3888-1/LTC3888-2 is a PMBus-compliant

dual loop DC/DC synchronous step-down switching regulator

controller with eight expandable phases supporting

a wide range of master/slave configurations. The controller

uses constant frequency current mode architecture to

provide excellent transient response and output regulation.

Each PWM master is capable of producing output voltages

from 0.3V to 3.45V with multiple phase configurations using

DrMOS devices that provide an output current monitor.

PMBus configuration and monitoring is supported by

LTpowerPlay? software. Programmable loop compensation

and built-in load step emulation facilitate setting bandwidth

based on input voltage and output load capacitance.

PMBus commands allow read back of input voltage, output

voltage and current, and operating status. Operating

parameters can be set via PMBus command or stored in

internal EEPROM for use at power up. Switching frequency,

phase configuration, output voltage (LTC3888/LTC3888-2),

output current limit (LTC3888-1) and device address can

also be set using external programming resistors.

FEATURES

- PMBus/I2C Compliant Serial Interface

- Monitor Voltage, Current, Temperature and Faults

- Digitally Program VOUT, Margins, UV, OV, Current

Limit, Soft-Start/Stop and Sequencing

- Expandable to >16 Phases

- 4.5V ≤ VIN ≤ 26.5V, 0.3V ≤ VOUT ≤ 3.45V

- ±0.5 Output Voltage Accuracy

- Programmable PWM Loop Compensation

- Accurate PolyPhase? Current Sharing

- Internal EEPROM with ECC and Fault Logging

- DrMOS Output Current Monitor Interface

- DrMOS Temperature/Fault Bus Interface

- DrMOS Gate Drive Supply Monitor

- Load Step Emulation

- Internal or External PWM Clock from 250kHz to 1MHz

- 52-Pin (5mm × 8mm) QFN Package

- AEC-Q100 Qualified for Automotive Applications

APPLICATIONS

- High Current Distributed Power Systems

- Servers, Network and Storage Equipment