PMBus Power-Supply Monitor Manages Eight DC-DC Converters

Targeted at automotive, medical, and telecommunication applications, the LTC2978 power supply monitor and controller performs digital management of up to eight 0- to 6-V power supplies. Using digital control over analog power supplies allows for quick adjustment of output voltages and precise protection, monitoring, and diagnostic mechanisms. The LTC2978’s PMBus-compliant interface provides simple access to an on-board EEPROM, giving users supply configuration, fault response, and logging capabilities. In addition, an integrated 15-bit ADC and 9:1 ADC MUX allows the IC to accurately monitor and servo eight output channels and one input channel. The primary PMBus operations include sequencing the startup of supplies, adjusting point-of-load voltages using voltage-buffered 10-bit current output digital-to-analog converters, margining voltages to programmed limits and supervising output voltages for overvalue or undervalue conditions. The configuration settings of these operations are all user-programmable and can be stored in EEPROM along with any faults, allowing for discontinuous system use. For applications that monitor more than eight supplies, the LTC2978 can be cascaded using only two connections. The LTC2978 is available in a 64-lead 9-mm x 9-mm QFN package that is RoHS compliant and specified over the commercial and industrial temperature ranges. Pricing starts at $10.95 each in 1000-piece quantities. LINEAR TECHNOLOGY CORP., Milpitas, CA. (408) 432-1900.