Polyphase Multifunction Energy Metering IC with Serial Port ADE7754 FEATURES the use of the ADE7754 in various power meter services such as High Accuracy, Supports IEC 687/61036 3-phase/4-wire, 3-phase/3-wire, and 4-wire delta. Compatible with 3-Phase/3-Wire, 3-Phase/4-Wire In addition to rms calculation, active and apparent power infor- and any Type of 3-Phase Services mation, the ADE7754 provides system calibration features for Less than 0.1% Error in Active Power Measurement over a each phase (i.e., channel offset correction, phase calibration, Dynamic Range of 1000 to 1 and gain calibration). The CF logic output provides instanta- Supplies Active Energy, Apparent Energy, Voltage RMS, neous active power information. Current RMS, and Sampled Waveform Data The ADE7754 has a waveform sample register that enables Digital Power, Phase, and Input Offset Calibration access to ADC outputs. The part also incorporates a detection On-Chip Temperature Sensor ( 4 C Typical after Calibration) circuit for short duration low or high voltage variations. The On-Chip User Programmable Thresholds for Line Voltage voltage threshold levels and the duration (number of half line SAG and Overdrive Detections cycles) of the variation are user programmable. SPI Compatible Serial Interface with Interrupt Request Line (IRQ) A zero-crossing detection is synchronized with the zero-crossing Pulse Output with Programmable Frequency point of the line voltage of each of the three phases. The infor- Proprietary ADCs and DSP Provide High Accuracy over mation collected is used to measure each lines period. It is also Large Variations in Environmental Conditions and Time used internally to the chip in the line active energy and line Single 5 V Supply apparent energy accumulation modes. This permits faster and more accurate calibration of the power calculations. This signal GENERAL DESCRIPTION is also useful for synchronization of relay switching. The ADE7754 is a high accuracy polyphase electrical energy Data is read from the ADE7754 via the SPI serial interface. The measurement IC with a serial interface and a pulse output. The interrupt request output (IRQ) is an open-drain, active low ADE7754 incorporates second order - ADCs, reference logic output. The IRQ output goes active low when one or more circuitry, temperature sensor, and all the signal processing interrupt events have occurred in the ADE7754. A status regis- required to perform active, apparent energy measurements, and ter indicates the nature of the interrupt. rms calculation. The ADE7754 is available in a 24-lead SOIC package. The ADE7754 provides different solutions for measuring active and apparent energy from the six analog inputs, thus enabling FUNCTIONAL BLOCK DIAGRAM RESET AV DD AVRMSOS AVGAIN ADE7754 AVAG 2 X POWER SUPPLY MONITOR AIRMSOS PGA1 AAPGAIN 2 I HPF X AP ADC LPF2 X I AN PGA2 V AAPOS AWG AP APHCAL ADC ABS BVRMSOS BVGAIN BVAG 2 X CFNUM BIRMSOS PGA1 BAPGAIN 2 HPF X I BP ADC X DFC CF LPF2 I BN PGA2 V BAPOS BWG BP ADC BPHCAL ABS CVRMSOS CVGAIN DV CFDEN DD CVAG 2 X DGND CLKIN CIRMSOS PGA1 CAPGAIN 2 CLKOUT HPF X I CP ADC WDIV VADIV X % % LPF2 I CN PGA2 V CAPOS CWG CP ADC CPHCAL ABS ADE7754 REGISTERS AND V N SERIAL INTERFACE TEMP 4k ADC 2.4V REF SENSOR AGND REF DIN DOUT SCLK CS IRQ IN/OUT REV. 0 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 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. may result from its use. No license is granted by implication or otherwise Tel: 781/329-4700 www.analog.com under any patent or patent rights of Analog Devices. Trademarks and Fax: 781/326-8703 2003 Analog Devices, Inc. All rights reserved. registered trademarks are the property of their respective companies.ADE7754 Contents ENERGIES SCALING 27 GENERAL DESCRIPTION . 1 CHECK SUM REGISTER . 27 FEATURES . 1 SERIAL INTERFACE 28 SPECIFICATIONS . 3 Serial Write Operation . 28 TIMING CHARACTERISTICS . 4 Serial Read Operation . 29 ABSOLUTE MAXIMUM RATINGS . 5 INTERRUPTS 30 ORDERING GUIDE 5 Using Interrupts with an MCU 30 PIN CONFIGURATION . 5 Interrupt Timing . 30 PIN FUNCTION DESCRIPTIONS 5 ACCESSING THE ADE7754 ON-CHIP REGISTERS 31 TYPICAL PERFORMANCE CHARACTERISTICS . 7 Communications Register 31 TERMINOLOGY . 9 Operational Mode Register (0Ah) 35 Measurement Error 9 Gain Register (18h) . 36 Phase Error Between Channels . 9 CFNUM Register (25h) 36 Power Supply Rejection . 9 Measurement Mode Register (0Bh) . 37 ADC Offset Error . 9 Waveform Mode Register (0Ch) . 37 Gain Error . 9 Watt Mode Register (0Dh) . 38 Gain Error Match . 9 VA Mode Register (0Eh) . 38 POWER SUPPLY MONITOR . 9 Interrupt Enable Register(0Fh) 39 ANALOG INPUTS . 9 Interrupt Status Register (10h)/Reset Interrupt Status ANALOG-TO-DIGITAL CONVERSION . 10 Register (11h) . 40 Antialias Filter . 10 OUTLINE DIMENSIONS . 41 CURRENT CHANNEL ADC 11 Current Channel ADC Gain Adjust . 11 Current Channel Sampling . 11 VOLTAGE CHANNEL ADC 12 ZERO-CROSSING DETECTION . 12 Zero-Crossing Timeout 13 PERIOD MEASUREMENT . 13 LINE VOLTAGE SAG DETECTION 13 PEAK DETECTION . 13 Peak Level Set . 14 TEMPERATURE MEASUREMENT 14 PHASE COMPENSATION 14 ROOT MEAN SQUARE MEASUREMENT . 15 Current RMS Calculation 15 Current RMS Gain Adjust 16 Current RMS Offset Compensation . 16 Voltage RMS Calculation . 16 Voltage RMS Gain Adjust 16 Voltage RMS Offset Compensation . 17 ACTIVE POWER CALCULATION . 17 Power Offset Calibration . 18 Reverse Power Information . 18 TOTAL ACTIVE POWER CALCULATION 18 ENERGY CALCULATION 19 Integration Times Under Steady Load . 20 Energy to Frequency Conversion . 20 No Load Threshold . 21 Mode Selection of the Sum of the Three Active Energies . 22 LINE ENERGY ACCUMULATION . 22 REACTIVE POWER CALCULATION . 23 TOTAL REACTIVE POWER CALCULATION 24 Reactive Energy Accumulation Selection . 24 APPARENT POWER CALCULATION 24 Apparent Power Offset Calibration . 25 TOTAL APPARENT POWER CALCULATION . 25 APPARENT ENERGY CALCULATION . 26 Integration Times under Steady Load . 26 LINE APPARENT ENERGY ACCUMULATION 26 2 REV. 0