ATT7022EU-N

ATT7022E/26E/28E series multi-function high-precision three-phase energy metering ICs, suitable for three-phase three-wire and three-phase four-wire applications. Integrating multiple second-order sigma-delta ADCs, reference voltage circuits, and DSP circuits for all power, energy, RMS, power factor, and frequency measurements, these chips can measure active power, reactive power, apparent power, active energy, and reactive energy for each phase and the combined phases. They also measure per-phase current and voltage RMS values, power factor, phase angle, frequency, and other parameters, fully meeting the requirements of three-phase multi-rate multi-function energy meters. Supports full digital-domain gain and phase correction, i.e., pure software calibration. Active and reactive energy pulse outputs CF1 and CF2 provide instantaneous active and reactive power information, and can be connected directly to a reference meter for error calibration. ATT7022E/26E provides two apparent power and energy metering modes: RMS apparent mode and PQS apparent mode. Apparent energy pulses are output via CF3 and can be connected to a reference meter for apparent energy error calibration. ATT7022E provides fundamental parameter metering: fundamental active power, fundamental active energy, and fundamental current and voltage RMS values. Pulse output CF4 provides instantaneous fundamental active power information, which can be used directly for fundamental calibration. An SPI interface is provided for convenient transfer of metering and calibration parameters between the chip and an external MCU. All metering and calibration parameters are readable via the SPI interface. The built-in voltage monitoring circuit ensures normal operation during power-up and power-down.

Key features

• High accuracy: nonlinearity measurement error less than 0.1% within input dynamic range (5000:1)
• Active energy measurement compliant with Class 0.2S and 0.5S, supporting IEC62053-22:2003 and GB/T17215.322-2008
• Reactive energy measurement compliant with Class 1 and Class 2, supporting IEC62053-23:2003 and GB/T17215.323-2008
• Fundamental active power/energy, voltage/current RMS, and CF pulse output
• RMS and PQS apparent power/energy metering (optional)
• Active, reactive, and apparent power/energy with CF pulse output
• Power factor, phase angle, line frequency, and voltage phase angle parameters
• Voltage and current RMS with accuracy better than 0.1% over 500:1 dynamic range
• Three-phase voltage vector sum and current vector sum RMS output
• Phase loss detection and voltage/current phase sequence detection
• Interrupt support: zero-crossing interrupt, sampling interrupt, energy pulse interrupt, calibration interrupt
• Active and reactive reverse power indication
• Combined-phase energy: absolute value summation or algebraic summation (selectable)
• Adjustable meter constant
• Adjustable startup current
• Accurate measurement of active, reactive, and apparent power/energy up to the 41st harmonic
• Gain and phase compensation, small-current nonlinearity compensation
• SPI interface up to 10Mbps
• Built-in temperature sensor
• Three-phase three-wire and three-phase four-wire mode support
• On-chip reference voltage with optional external reference
• Synchronized sampling data for sub-harmonic analysis without preprocessing (ATT7022E)
• 1k×16-bit ADC data buffer
• Pulse doubling function for small-signal meter calibration
• ROSI coil support
• LQFP44 package
• 3.3V supply
• Crystal 5.5296MHz