Datasheet ADE7756 Datasheet (ANALOG DEVICES)

The World Leader in High Performance Signal Processing Solutions

Single-phase Energy Metering IC

with Pulse Output

ADE7756

Precision Converters (PRC) Division

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ADE7756: A programmable solution for

Energy measurement

• ADE7756 application ◄

• Block Diagram

• Quality

• Features

• Analog Front end

• Current sensor connection

• Digital calibration

• Energy measurement

• Zero crossing

• SAG detection

• Calibration Mode

• Waveform sampling

• Temperature sensor

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Technology at a glance

• ADE7756 application

• Block Diagram ◄

• Quality

• Features

• Analog Front end

• Current sensor connection

• Digital calibration

• Energy measurement

• Zero crossing

• SAG detection

• Calibration Mode

• Waveform sampling

• Temperature sensor

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Single Chip Energy Meter

Lowest Cost Single Phase Measurement

• ADE7756 application

• Block Diagram

• Quality ◄

• Features

• Analog Front end

• Current sensor connection

• Digital calibration

• Energy measurement

• Zero crossing

• SAG detection

• Calibration Mode

• Waveform sampling

• Temperature sensor

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ADE7756: Block Diagram

• ADE7756 application

• Block Diagram

• Quality

• Features ◄

• Analog Front end

• Current sensor connection

• Digital calibration

• Energy measurement

• Zero crossing

• SAG detection

• Calibration Mode

• Waveform sampling

• Temperature sensor

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ADE7756: A validated Analog front end

• ADE7756 application

• Block Diagram

• Quality

• Features

• Analog Front end ◄

• Current sensor connection

• Digital solution

• Energy measurement

• Zero crossing

• SAG detection

• Calibration Mode

• Waveform sampling

• Temperature sensor

• 16-bit resolution from 2ndorder ΣΔ ADC

• Linearity error < 0.3% over 1:1000 dynamic range (int. reference)

• Measurement Bandwidth 14 kHz

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ADE7756: Easy use of Current sensors+

• ADE7756 application

• Block Diagram

• Quality

• Features

• Analog Front end

• Current sensor connection ◄

• Digital solution

• Energy measurement

• Zero crossing

• SAG detection

• Calibration Mode

• Waveform sampling

• Temperature sensor

• Differential input

• Input Gain up to 64 to interface low shunt resistor

Gain of 16 recommended for 100μΩ

• Phase compensation for CT connection

+/-2.5°max in 0.091°increment @ 50Hz

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ADE7756: A Digital solution

• ADE7756 application

• Block Diagram

• Quality

• Features

• Analog Front end

• Current sensor connection

• Digital solution ◄

• Energy measurement

• Zero crossing

• SAG detection

• Calibration Mode

• Waveform sampling

• Temperature sensor

• No manual calibration

• Configuration done by writing ADE7756 registers at power up

• Only one point calibration to reach 0.3% accuracy

• SPI interface up to 5MHz

• CF output to drive LED

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ADE7756: Energy measurement

• ADE7756 application

• Block Diagram

• Quality

• Features

• Analog Front end

• Current sensor connection

• Digital solution

• Energy measurement ◄

• Zero crossing

• SAG detection

• Calibration Mode

• Waveform sampling

• Temperature sensor

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•Accumulation of the Active Energy in a 40-bit register

=> Equivalent to 11.5s of Energy at Full scale

•HPF filter eliminates any DC offset

•Gain for calibration and multi-rate billing

(APGAIN + CFDIV)

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ADE7756: Line Voltage supervisory (1)

• ADE7756 application

• Block Diagram

• Quality

• Features

• Analog Front end

• Current sensor connection

• Digital solution

• Energy measurement

• Zero crossing ◄

• SAG detection

• Calibration Mode

• Waveform sampling

• Temperature sensor

Detect Zero-crossing on CH2 => Drive ZX pin and IRQ

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Applications:

• On-chip Watch Dog timer

• Phase information of the

voltage channel

• Interface with a Power

switch to cut power at low
current

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ADE7756: Line Voltage supervisory (2)

• ADE7756 application

• Block Diagram

• Quality

• Features

• Analog Front end

• Current sensor connection

• Digital solution

• Energy measurement

• Zero crossing

• SAG detection ◄

• Calibration Mode

• Waveform sampling

• Temperature sensor

Detect Level variation on CH2 => Drive SAG pin or IRQ

SAG Level and detection time configurable

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ADE7756: High Speed and accurate Energy measurement

• ADE7756 application

• Block Diagram

• Quality

• Features

• Analog Front end

• Current sensor connection

• Digital solution

• Energy measurement

• Zero crossing

• SAG detection

• Calibration Mode ◄

• Waveform sampling

• Temperature sensor

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• Principle: Accumulation of the Active Energy over

N half line cycles (<255) => Drive IRQ when finished

Benefits:

• Cancel the ripple frequency effect (2 x line freq) in Energy

Measurement

• Shorten calibration time-Easy solution to detect Energy placed back

on the grid (Sign only)

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ADE7756: ADC outputs available through SPI port

• ADE7756 application

• Block Diagram

• Quality

• Features

• Analog Front end

• Current sensor connection

• Digital solution

• Energy measurement

• Zero crossing

• SAG detection

• Calibration Mode

• Waveform sampling ◄

• Temperature sensor

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CH1 or CH2 or Multiplication results available through the
WAVEFORM register (24-bit)

Equivalent sampling frequency = 28 ksps

• Use the ADE7756 as an ADC in addition to Energy measurement

=> Vrms or Irms calculation on a μP

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ADE7756: Embedded Temperature sensor

• ADE7756 application

• Block Diagram

• Quality

• Features

• Analog Front end

• Current sensor connection

• Digital solution

• Energy measurement

• Zero crossing

• SAG detection

• Calibration Mode

• Waveform sampling

• Temperature sensor ◄

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8-bit register : 1LSB/°C

• Temperature compensation of external components

• Temperature supervisory of the system

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