Poly Phase Multifunction Energy Metering IC
with Per Phase Information
ADE7758
FEATURES
High accuracy, supports IEC 60687, IEC 61036, IEC 61268,
IEC 62053-21, IEC 62053-22, and IEC 62053-23
Compatible with 3-phase/3-wire, 3-phase/4-wire, and other
3-phase services
Less than 0.1% active energy error over a dynamic range of
1000 to 1 at 25°C
Supplies active/reactive/apparent energy, voltage rms,
current rms, and sampled waveform data
Two pulse outputs, one for active power and the other
selectable between reactive and apparent power with
programmable frequency
Digital power, phase, and rms offset calibration
On-chip user programmable thresholds for line voltage SAG
and overvoltage detections
On-chip digital integrator enables direct interface-to-current
sensors with di/dt output
A PGA in the current channel allows direct interface to
shunts and current transformers
A SPI® compatible serial interface with IRQ
Proprietary ADCs and DSP provide high accuracy over large
variations in environmental conditions and time
Reference 2.4 V (drift 30 ppm/°C typ) with external
overdrive capability
Single 5 V supply, low power (70 mW typ)
GENERAL DESCRIPTION
The ADE7758
1
is a high accuracy 3-phase electrical energy
measurement IC with a serial interface and two pulse outputs.
The ADE7758 incorporates second-order ∑-∆ ADCs, a digital
integrator, reference circuitry, temperature sensor, and all the
signal processing required to perform active, reactive, and
apparent energy measurement and rms calculations.
The ADE7758 is suitable to measure active, reactive, and
apparent energy in various 3-phase configurations, such as
WYE or DELTA services, both with three or four wires. The
ADE7758 provides system calibration features for each phase,
i.e., rms offset correction, phase calibration, and power
calibration. The APCF logic output gives active power
information, and the VARCF logic output provides
instantaneous reactive or apparent power information.
(Continued on Page 4)
FUNCTIONAL BLOCK DIAGRAM
AVDD
4
REF
IN/OUT
12
AGND
11
POWER
SUPPLY
MONITOR
X
2
AVAG[11:0]
AVRMSGAIN[11:0]
AVRMSOS[11:0]
X
2
LPF
AIGAIN[11:0]
90
°
PHASE
SHIFTING FILTER
dt
HPF
INTEGRATOR
AIRMSOS[11:0]
4kΩ
ADE7758
2.4V
REF
PGA1
+
REACTIVE OR
APPARENT POWER
VARCFNUM[11:0]
DFC
IAP
5
IAN
6
ADC
–
PGA2
+
ADC
–
PGA1
+
ADC
IBN
8
VBP
15
PGA1
+
–
PGA2
+
ADC
VN
13
–
–
PGA2
+
ADC
–
ADC
ICN
10
VCP
14
ICP
9
π
2
÷
17
VARCF
LPF2
AVAROS[11:0]
AVARG[11:0]
VARCFDEN[11:0]
VAP
16
Φ
LPF2
APHCAL[6:0]
AWATTOS[11:0]
AWG[11:0]
PHASE B
AND
PHASE C
DATA
IBP
7
ACTIVE/REACTIVE/APPARENT ENERGIES
AND VOLTAGE/CURRENT RMS CALCULATION
FOR PHASE B
(SEE PHASE A FOR DETAILED SIGNAL PATH)
VADIV[7:0]
VARDIV[7:0]
WDIV[7:0]
%
%
%
ADE7758 REGISTERS AND
SERIAL INTERFACE
ACTIVE POWER
APCFNUM[11:0]
DFC
÷
1
3
APCF
DVDD
DGND
ACTIVE/REACTIVE/APPARENT ENERGIES
AND VOLTAGE/CURRENT RMS CALCULATION
FOR PHASE C
(SEE PHASE A FOR DETAILED SIGNAL PATH)
APCFDEN[11:0]
2
19
CLKIN
20
CLKOUT
22
24
23
21
18
04443-0-001
DIN
1
DOUT
SCLK
CS
IRQ
Patents Pending.
Figure 1.
Rev. A
Information furnished by Analog Devices is believed to be accurate and reliable.
However, no responsibility is assumed by Analog Devices for its use, nor for any
infringements of patents or other rights of third parties that may result from its use.
Specifications subject to change without notice. No license is granted by implication
or otherwise under any patent or patent rights of Analog Devices. Trademarks and
registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.326.8703
© 2004 Analog Devices, Inc. All rights reserved.
AD [ ANALOG DEVICES ]
