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Data Sheet
Polyphase Multifunction Energy Metering IC with Harmonic and Fundamental Information
ADE7854/ADE7858/ADE7868/ADE7878
FEATURES
Highly accurate; supports EN 50470-1, EN 50470-3, IEC 62053-21, IEC 62053-22, and IEC 62053-23 standards
Compatible with 3-phase, 3- or 4-wire (delta or wye), and other 3-phase services
Supplies total (fundamental and harmonic) active, reactive (ADE7878, ADE7868, and ADE7858 only), and apparent energy, and fundamental active/reactive energy (ADE7878 only) on each phase and on the overall system
Less than 0.1% error in active and reactive energy over a dynamic range of 1000 to 1 at TA = 25°C
Less than 0.2% error in active and reactive energy over a dynamic range of 3000 to 1 at TA = 25°C
Supports current transformer and di/dt current sensors Dedicated ADC channel for neutral current input (ADE7868 and
ADE7878 only) Less than 0.1% error in voltage and current rms over a
dynamic range of 1000 to 1 at TA = 25°C Supplies sampled waveform data on all three phases and on
neutral current Selectable no load threshold levels for total and
fundamental active and reactive powers, as well as for apparent powers Low power battery mode monitors phase currents for antitampering detection (ADE7868 and ADE7878 only) Battery supply input for missing neutral operation Phase angle measurements in both current and voltage channels with a typical 0.3° error Wide-supply voltage operation: 2.4 V to 3.7 V Reference: 1.2 V (drift +5 ppm/°C typical) with external overdrive capability Single 3.3 V supply 40-lead lead frame chip scale package (LFCSP), Pb-free Operating temperature: −40°C to +85°C Flexible I2C, SPI, and HSDC serial interfaces
APPLICATIONS
Energy metering systems
GENERAL DESCRIPTION
The ADE7854/ADE7858/ADE7868/ADE7878 are high accuracy, 3-phase electrical energy measurement ICs with serial interfaces and three flexible pulse outputs. The ADE78xx devices incorporate second-order sigma-delta (Σ-∆) analog-to-digital converters (ADCs), a digital integrator, reference circuitry, and all of the signal processing required to perform total (fundamental and
harmonic) active, reactive (ADE7878, ADE7868, and ADE7858), and apparent energy measurement and rms calculations, as well as fundamental-only active and reactive energy measurement (ADE7878) and rms calculations. A fixed function digital signal processor (DSP) executes this signal processing. The DSP program is stored in the internal ROM memory.
The ADE7854/ADE7858/ADE7868/ADE7878 are suitable for measuring active, reactive, and apparent energy in various 3-phase configurations, such as wye or delta services, with both three and four wires. The ADE78xx devices provide system calibration features for each phase, that is, rms offset correction, phase calibration, and gain calibration. The CF1, CF2, and CF3 logic outputs provide a wide choice of power information: total active, reactive, and apparent powers, or the sum of the current rms values, and fundamental active and reactive powers.
The ADE7854/ADE7858/ADE7868/ADE7878 contain waveform sample registers that allow access to all ADC outputs. The devices also incorporate power quality measurements, such as short duration low or high voltage detections, short duration high current variations, line voltage period measurement, and angles between phase voltages and currents. Two serial interfaces, SPI and I2C, can be used to communicate with the ADE78xx. A dedicated high speed interface, the high speed data capture (HSDC) port, can be used in conjunction with I2C to provide access to the ADC outputs and real-time power information. The ADE7854/ADE7858/ADE7868/ADE7878 also have two interrupt request pins, IRQ0 and IRQ1, to indicate that an enabled
interrupt event has occurred. For the ADE7868/ADE7878, three specially designed low power modes ensure the continuity of energy accumulation when the ADE7868/ADE7878 is in a tampering situation. See Table 1 for a quick reference chart listing each part and its functions. The ADE78xx are available in the 40-lead LFCSP, Pb-free package.
Table 1. Part Comparison
Part No.
IRMS, VRMS, and WATT VAR VA
ADE7878 Yes
Yes Yes
ADE7868 Yes
Yes Yes
ADE7858 Yes
Yes Yes
ADE7854 Yes
No Yes
di/dt
Yes Yes Yes Yes
Fundamental WATT and VAR
Yes
No
No
No
Tamper Detect and Low Power Modes
Yes
Yes
No
No
Rev. H
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