Energy metering IC for single-phase revenue-grade meters
The AD7751AN is a single-phase energy metering IC from Analog Devices' AD7751 series, designed for utility-grade power measurement in residential and light commercial meters. Measurement error is 0.1% across the dynamic range, which meets the accuracy floor for Class 1 revenue metering per IEC 62053-21 without external calibration trimming.
Input impedance and sensor interface
The 400 kOhm input impedance presents a light load to the current sensor — a shunt resistor or current transformer secondary sees minimal burden, preserving the sensor's phase-angle accuracy across the load range. Logic thresholds are set at 0.8 V / 2.4 V for the low and high input levels respectively, compatible with 5 V CMOS and TTL interfaces without external level shifting.
Temperature grade and deployment environment
The 24-pin PDIP package (24-DIP, 0.300" width, 7.62 mm row spacing) is a through-hole footprint that survives manual rework and field replacement without hot-air equipment — a practical choice for serviceable meter designs.
Cross-reference to AD7751AAN and AD7755AN
The AD7751AAN shares the same 0.1% error, 400 kOhm input impedance, and 24-DIP package — the only difference is a 2.4 V supply voltage vs the AD7751AN's 4.5-5.5 V range. A board designed for the AD7751AN's 5 V rail will not run the AD7751AAN without a regulator change.