Add PMBus digital manager module to monitor 16 analogue PSUs

May 05, 2014 // By Graham Prophet
LTM2987 is a highly integrated 16-channel µModule (micromodule) PMBus power system manager, which adds extensive digital control and monitoring to an analogue power system.

Software-based configuration and measurement of power system performance reduces development time, enhances system reliability and enables finely optimised board energy consumption. The device trims, margins and monitors supply outputs with ±0.25% voltage accuracy, raising circuit board yields and long-term reliability. Supply sequencing (timed and tracking), supervision and EEPROM fault-logging are also built in. All basic passive components – low-pass RC filters, bypass capacitance and pull-up resistors – are integrated. The high functional and component integration reduces solution footprint, shortens the bill of materials and eases routing on large rail-count ASIC, DSP and FPGA boards in servers, network routers and industrial test equipment.

A 16-bit ADC in the LTM2987 measures supply output voltages, input voltage and device temperature. Fast under- and over-voltage supervisors prevent system malfunction and damage. Faults trigger EEPROM black box recording, which simplifies failure analysis while providing insight into future system improvements. Multiple Power System Managers can be cascaded to sequence and fault-manage more than 16 rails. Over one hundred PMBus compatible commands are provided for flexible programming and data readback of the power system. Register configuration is accomplished through the LTpowerPlay development environment, which supports all Linear Technology digital Power System Management (PSM) devices. Once programmed, no software coding is needed for autonomous operation.

Specified over the 0°C to 70°C commercial and -40°C to 105°C industrial temperature range, the LTM2987 comes in a 144-pin 15 x 15 mm BGA for $23.95 (1000).

Linear Technology; www.linear.com/product/LTM2987