Datasheet ADE7758 (Analog Devices) - 4

ADE7758 Data Sheet GENERAL DESCRIPTION
The ADE7758 has a waveform sample register that allows access Data is read from the ADE7758 via the SPI serial interface. The to the ADC outputs. The part also incorporates a detection interrupt request output (IRQ) is an open-drain, active low logic circuit for short duration low or high voltage variations. The output. The IRQ output goes active low when one or more voltage threshold levels and the duration (number of half-line interrupt events have occurred in the ADE7758. A status register cycles) of the variation are user programmable. A zero-crossing indicates the nature of the interrupt. The ADE7758 is available detection is synchronized with the zero-crossing point of the in a 24-lead SOIC package. line voltage of any of the three phases. This information can be used to measure the period of any one of the three voltage inputs. The zero-crossing detection is used inside the chip for the line cycle energy accumulation mode. This mode permits faster and more accurate calibration by synchronizing the energy accumulation with an integer number of line cycles. Rev. E | Page 4 of 72 Document Outline FEATURES GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM TABLE OF CONTENTS GENERAL DESCRIPTION SPECIFICATIONS TIMING CHARACTERISTICS TIMING DIAGRAMS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TERMINOLOGY TYPICAL PERFORMANCE CHARACTERISTICS TEST CIRCUITS THEORY OF OPERATION ANTIALIASING FILTER ANALOG INPUTS CURRENT CHANNEL ADC Current Channel Sampling di/dt CURRENT SENSOR AND DIGITAL INTEGRATOR PEAK CURRENT DETECTION Peak Current Detection Using the PEAK Register OVERCURRENT DETECTION INTERRUPT VOLTAGE CHANNEL ADC Voltage Channel Sampling ZERO-CROSSING DETECTION Zero-Crossing Timeout PHASE COMPENSATION PERIOD MEASUREMENT LINE VOLTAGE SAG DETECTION SAG LEVEL SET PEAK VOLTAGE DETECTION Peak Voltage Detection Using the VPEAK Register Overvoltage Detection Interrupt PHASE SEQUENCE DETECTION POWER-SUPPLY MONITOR REFERENCE CIRCUIT TEMPERATURE MEASUREMENT ROOT MEAN SQUARE MEASUREMENT Current RMS Calculation Current RMS Offset Compensation Voltage Channel RMS Calculation Voltage RMS Offset Compensation Voltage RMS Gain Adjust ACTIVE POWER CALCULATION Active Power Gain Calibration Active Power Offset Calibration Sign of Active Power Calculation No-Load Threshold Active Energy Calculation Integration Time Under Steady Load Energy Accumulation Mode Active Power Frequency Output Line Cycle Active Energy Accumulation Mode REACTIVE POWER CALCULATION Reactive Power Gain Calibration Reactive Power Offset Calibration Sign of Reactive Power Calculation Reactive Energy Calculation Integration Time Under Steady Load Energy Accumulation Mode Reactive Power Frequency Output Line Cycle Reactive Energy Accumulation Mode APPARENT POWER CALCULATION Apparent Power Gain Calibration Apparent Power Offset Calibration Apparent Energy Calculation Integration Time Under Steady Load Energy Accumulation Mode Apparent Power Frequency Output Line Cycle Apparent Energy Accumulation Mode ENERGY REGISTERS SCALING WAVEFORM SAMPLING MODE CALIBRATION Calibration Using Pulse Output Gain Calibration Using Pulse Output Example: Watt Gain Calibration of Phase A Using Pulse Output Phase Calibration Using Pulse Output Example: Phase Calibration of Phase A Using Pulse Output Power Offset Calibration Using Pulse Output Example: Offset Calibration of Phase A Using Pulse Output Calibration Using Line Accumulation Gain Calibration Using Line Accumulation Example: Watt Gain Calibration Using Line Accumulation Phase Calibration Using Line Accumulation Example: Phase Calibration Using Line Accumulation Power Offset Calibration Using Line Accumulation Example: Power Offset Calibration Using Line Accumulation Calibration of IRMS and VRMS Offset Example: Calibration of RMS Offsets CHECKSUM REGISTER INTERRUPTS USING THE INTERRUPTS WITH AN MCU INTERRUPT TIMING SERIAL INTERFACE SERIAL WRITE OPERATION SERIAL READ OPERATION ACCESSING THE ON-CHIP REGISTERS REGISTERS COMMUNICATIONS REGISTER OPERATIONAL MODE REGISTER (0x13) MEASUREMENT MODE REGISTER (0x14) WAVEFORM MODE REGISTER (0x15) COMPUTATIONAL MODE REGISTER (0x16) LINE CYCLE ACCUMULATION MODE REGISTER (0x17) INTERRUPT MASK REGISTER (0x18) INTERRUPT STATUS REGISTER (0x19)/RESET INTERRUPT STATUS REGISTER (0x1A) OUTLINE DIMENSIONS ORDERING GUIDE