Monitoring circuit board power and energy use is a prerequisite for managing, optimising and reducing energy consumption in order to lower server rack and data center cooling and utility costs.
The Power by Linear LTC2972 is a dual channel power system manager that provides the input energy, reported in joules, and the elapsed time through a PMBus interface. When combined with digital measurements of POL output voltages, currents, and power, the device enables long-term monitoring of a power system’s conversion efficiency. This allows comprehensive software-based monitoring and control of the power sub-systems of FPGA, ASIC, and DSP boards, enhancing system reliability and allowing the real time optimisaion of board energy consumption.
Supply output voltages are trimmed, margined, and monitored using a 16bit analogue-to-digital converter (ADC) with 0.25% total unadjusted error (TUE), improving board yields and long-term performance. Supply output currents are measured using a sense resistor, inductor DCR, or the I MON output of a power supply.
Supply sequencing, supervision, and EEPROM fault-logging are built in. Faults trigger EEPROM black box recording, simplifying failure analysis while providing insight into future system improvements. Programmable power good, or general-purpose input/output (GPIO), pins are available with each channel. The LTC2972 connects with other power system managers to coordinate sequencing and fault management of more than two rails. PMBus-compatible commands are used for flexible programming and data readback of the power system.
Configuration is handled through the LTpowerPlay development environment, which supports all Power by Linear power system management (PSM) devices. Once programmed, no software coding is needed for autonomous operation.
Specified over the 0ºC to 70ºC commercial and −40ºC to 105ºC industrial temperature ranges, the LTC2972 comes in a 44-pin 6mm x 7mm QFN package with prices starting from US$3.99 in volume. Device samples and evaluation circuit boards are available online.