DESCRIPTION

The LTC?2977 is an 8-channel Power System Manager

used to sequence, trim (servo), margin, supervise,

manage faults, provide telemetry and create fault logs.

PMBus commands support power supply sequencing,

precision point-of-load voltage adjustment and margining.

DACs use a proprietary soft-connect algorithm to

minimize supply disturbances. Supervisory functions

include overvoltage and undervoltage threshold limits

for eight power supply output channels and one power

supply input channel, as well as over and under temperature

limits. Programmable fault responses can disable the

power supplies with optional retry after a fault is detected.

Faults that disable a power supply can automatically trigger

black box EEPROM storage of fault status and associated

telemetry. An internal 16-bit ADC monitors eight

output voltages, one input voltage, and die temperature.

In addition, odd numbered channels can be configured

to measure the voltage across a current sense resistor. A

programmable watchdog timer monitors microprocessor

activity for a stalled condition and resets the microprocessor

if necessary. A single wire bus synchronizes power

supplies across multiple LTC Power System Management

(PSM) devices. Configuration EEPROM with ECC supports

autonomous operation without additional software.

FEATURES

- Sequence, Trim, Margin and Supervise Eight Power

Supplies

- Manage Faults, Monitor Telemetry and Create Fault Logs

- PMBus? Compliant Command Set

- Supported by LTpowerPlay? GUI

- Margin or Trim Supplies to Within 0.25 of Target

- Fast OV/UV Supervisors Per Channel

- Coordinate Sequencing and Fault Management

Across Multiple LTC PSM Devices

- Automatic Fault Logging to Internal EEPROM

- Operate Autonomously without Additional Software

- Internal Temperature and Input Voltage Supervisors

- Accurate Monitoring of Eight Output Voltages, Input

Voltage and Internal Die Temperature

- I2C/SMBus Serial Interface

- Can Be Powered from 3.3V, or 4.5V to 15V

- Programmable Watchdog Timer

- 100 Pin-Compatible Upgrade to the LTC2978/LTC2978A

- Available in 64-Pin 9mm × 9mm QFN Package

- AEC-Q100 Qualified for Automotive Applications

APPLICATIONS

- Computers and Network Servers

- Industrial Test and Measurement

- High Reliability Systems

- Medical Imaging

- Video