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