The AD7751 is an energy metering IC with built-in fault detection. This chip supports high-precision measurement at 50Hz/60Hz, with a dynamic range of 500:1 and an error rate of less than 0.1%. It can provide average real power and outputs it through frequency outputs F1 and F2. It also has a high-frequency output CF for calibration and continuous monitoring of phase and neutral currents, allowing fault detection in two-wire distribution systems. During a fault condition, the AD7751 uses the larger of the two currents (phase or neutral) for billing. Additionally, it has two logic outputs (FAULT and REVP).
The AD7751 is a high‑accuracy, fault‑tolerant energy‑metering integrated circuit designed for two‑wire distribution systems. It provides average real‑power outputs (F1, F2) for driving counters or stepper motors, a calibration‑oriented CF output, and logic signals for fault detection and reverse power detection.
The document includes full electrical specifications, absolute‑maximum ratings, pin descriptions, functional block diagrams, and theory of operation. It also lists ordering information for DIP and SSOP packages and explains the internal ADC, DSP, and on‑chip reference architecture.
| Measurement Error (Gain 1‑16) | 0.1 % typical |
|---|---|
| Bandwidth | 14 kHz typ |
| On‑Chip Reference Voltage | 2.5 V nominal |
| Supply Voltage (AVpp/DVpp) | 5 V ±5 % |
The analog and digital supply pins must be held at 5 V ±5 % for specified performance.