Digital power monitors with PMBus Interface measure voltage differences

01-06-2015 | Mouser Electronics | Test & Measurement

Mouser is now stocking the Analog Devices ADM1293 and ADM1294 digital power monitors with PMBus Interface. The high-accuracy, integrated digital power monitors provide digital current, voltage, and power monitoring using an on-chip, 12-bit analog-to-digital converter (ADC), communicated through a PMBus-compliant I2C interface. Both devices use an external sense resistor to determine current by measuring voltage differences. The internal 12-bit ADC amplifies and digitizes the voltage, and can also simultaneously sample primary and auxiliary input voltage. The internal digital block performs multiplication of the current and primary input voltage to calculate power, and the devices feature a power accumulator to meter energy. An industry-standard PMBus interface enables a master controller to read back the data from the device. The master controller combines the information with a known sense resistor value to calculate the current, voltage, power, and energy consumption over time on the monitored rail. The ADM1293 and ADM1294 are rated for -40C to 125C. The ADM1293 is designed for high-side supply monitoring (0V to 20V), and the ADM1294 is designed for low-side supply monitoring (-48V to 0V, with integrated shunt regulator).