Polyphase Multifunction Energy Metering IC
with per Phase Active and Reactive Powers
ADE7878
FEATURES
GENERAL DESCRIPTION
The ADE78781 is a high accuracy, 3-phase electrical energy
measurement IC with serial interfaces and three flexible pulse
outputs. The ADE7878 incorporates second-order sigma-delta
(Σ-Δ) analog-to-digital converters (ADCs), a digital integrator,
reference circuitry, and all the signal processing required to
perform total (fundamental and harmonic) active, reactive, and
apparent energy measurement and rms calculations, as well as
fundamental only active and reactive energy measurement and
rms calculations. A fixed function digital signal processor (DSP)
executes this signal processing. The DSP program is stored into
internal ROM memory.
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/
apparent energy and fundamental active/reactive energy
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
Less than 0.1% error in voltage and current rms over a
dynamic range of 1000 to 1 at TA = 25°C
The ADE7878 is 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 ADE7878
provides 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.
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
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 10 ppm/°C typical) with external
overdrive capability
The ADE7878 contains waveform sample registers that allow
access to all ADC outputs. The device also incorporates 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 ADE7878. 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 ADE7878 also has two
Single 3.3 V supply
40-lead lead frame chip scale package (LFCSP), Pb-free
Operating temperature: −40° to +85°C
Flexible I2C, SPI, and HSDC serial interfaces
APPLICATIONS
IRQ0
IRQ1
interrupt request pins,
and
, to indicate that an
Energy metering systems
enabled interrupt event has occurred. For the ADE7878, three
specially designed low power modes ensure the continuity of
energy accumulation when the ADE7878 is in a tampering
situation.
The ADE7878 is available in a 40-lead LFCSP, Pb-free package.
1 U.S. patents pending.
Rev. 0
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rights of third parties that may result from its use. Specifications subject to change without notice. No
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