GENERAL DESCRIPTION

The ADE7761A is a high accuracy, fault-tolerant, electrical energy measurement IC intended for use with 2-wire distribution systems. The part specifications surpass the accuracy requirements as quoted in the IEC 62053-21 standard. The only analog circuitry used on the ADE7761A is in the ADCs and reference circuit. All other signal processing (such as multiplication and filtering) is carried out in the digital domain. This approach provides superior stability and accuracy over extremes in environmental conditions and over time. The ADE7761A incorporates a fault detection scheme similar to the ADE7751 by continuously monitoring both phase and neutral currents. A fault is indicated when the currents differ by more than 6.25.

FEATURES

High accuracy, active energy measurement IC supports

IEC 62053-21

Less than 0.1 error over a dynamic range of 500 to 1

Supplies active power on the frequency outputs, F1 and F2

High frequency output CF is intended for calibration and

supplies instantaneous active power

Continuous monitoring of the phase and neutral current

allows fault detection in 2-wire distribution systems

Current channels input level best suited for shunt and

current transformer sensors

Uses the larger of the two currents (phase or neutral) to

bill—even during a fault condition

Continuous monitoring of the voltage and current inputs

allows missing neutral detection

Uses one current input (phase or neutral) to bill when

missing neutral is detected

Two logic outputs (FAULT and REVP) can be used to indicate

a potential miswiring, fault, or missing neutral condition

Direct drive for electromechanical counters and 2-phase

stepper motors (F1 and F2)

Proprietary ADCs and DSP provide high accuracy over large

variations in environmental conditions and time

Reference 2.5 V ± 8 (drift 30 ppm/°C typical) with external

overdrive capability

Single 5 V supply, low power