8-Channel Power System Manager Unrivaled ±0.25% Measurement Accuracy Increases System Efficiency The LTC®2977 PMBus Power System Manager with EEPROM provides complete digital power management of power supply systems with eight or more rails. The LTC2977 utilizes an I2C interface and PMBus command set to monitor, supervise, sequence, margin, fault manage and fault log positive or negative supplies. This provides rapid troubleshooting and debug capabilities during power system design, development, production and failure analysis. Power supply channels can be sequenced on or off using programmable time delays, while dedicated voltage supervisors on each channel provide precise thresholds and fast response times to protect loads from electrical overstress. All of the LTC2977’s functions perform with uncompromised accuracy, including better than ±0.25% total unadjusted error on ADC telemetry, and 0.25% margining and trimming accuracy on each supply. Users can harness the powerful LTpowerPlay™ GUI to configure and interrogate the LTC2977’s registers, user settings and fault log. Once configured, the LTC2977 provides the essential system management functions without host intervention and does not require writing a single line of code. Features n n n n n n n n n n n n Trim/Margin Eight Supplies to 0.25% Accuracy EEPROM for Configuration and Black Box Fault Logging I2C/SMBus Interface, PMBus Command Set Supported by LTpowerPlay GUI Supply Sequencer, Time Based or Tracking Monitor (16-Bit ADC) and Supervise (12µs Fast): −− Input and Eight Supply Voltages −− Optional Current Monitor on Odd Channels −− Die Temperature Coordinate Sequencing and Fault Management Across Managers Watchdog Timer Operates Autonomously without Additional Software –40°C to 105°C Operation 100% Pin-Compatible Upgrade to the LTC2978/ LTC2978A 64-Pin 9mm × 9mm QFN Package 4.5V < VIBUS < 15V** VIN VPWR VIN_SNS 3.3V** VDD33 VDACP0 TO INTERMEDIATE BUS CONVERTER ENABLE VIN_EN VSENSEP0 SDA PMBus INTERFACE LTC2977* SCL VOUT LOAD DIGITALLY MANAGED POWER SUPPLY VFB VDACM0 ALERTB VSENSEM0 SGND CONTROL0 VOUT_EN0 RUN/SS GND WRITE-PROTECT TO/FROM OTHER LTC POWER SUPPLY MANAGERS WP PWRGD WDI/RESETB FAULTB00 ASEL0 SHARE_CLK ASEL1 L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and LTpowerPlay is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. GND TO µP RESETB INPUT WATCHDOG TIMER INTERRUPT * SOME DETAILS OMITTED FOR CLARITY ONLY ONE OF EIGHT CHANNELS SHOWN ** MAY BE POWERED FROM EITHER AN EXTERNAL 3.3V SUPPLY OR THE INTERMEDIATE BUS Complete Development Platform with LTpowerPlay GUI lay rP LTpowe For Prototyping and Debug FREE Download www.linear.com/LTpowerPlay USB DC1613 USB to PMBus Controller DC2028 LTC2977 Demo Board Demonstration Board SYSTEM TREE CONFIGURATION SETTINGS OSCILLOSCOPE LIKE TELEMETRY DISPLAY Customer Board with LTC2977 In-Circuit Serial Programming or TELEMETRY DATA IDEALIZED POWER SUPPLY WAVEFORMS CONTEXT SENSITIVE DISPLAY OF SELECTED PARAMETERS DEVICE DASHBOARD FAULT SHARING CONFIGURATION www.linear.com/LTC2977 n 1-800-4-LINEAR 0513