ADE7761BARS-REF AD [Analog Devices], ADE7761BARS-REF Datasheet
ADE7761BARS-REF
Related parts for ADE7761BARS-REF
ADE7761BARS-REF Summary of contents
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FEATURES High accuracy, active energy measurement IC supports IEC 62053-21 Less than 0.1% error over a dynamic range of 1000 to 1 Supplies active power on the frequency outputs, F1 and F2 High frequency output CF is intended for calibration ...
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ADE7761B TABLE OF CONTENTS Features .............................................................................................. 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Characteristics ................................................................ 4 Absolute Maximum Ratings............................................................ 5 Performance Issues That May Affect Billing Accuracy........... 5 ESD Caution.................................................................................. ...
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SPECIFICATIONS ± 5%, AGND = DGND = 0 V, on-chip reference, on-chip oscillator Table 1. Parameter 1 ACCURACY 2 Measurement Error Phase Error Between Channels PF = 0.8 Capacitive PF = 0.5 Inductive 2 ...
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ADE7761B Parameter 5 LOGIC INPUTS PGA, SCF, S1, and S0 Input High Voltage, V INH Input Low Voltage, V INL Input Current Input Capacitance LOGIC OUTPUTS CF, REVP, and FAULT Output High Voltage ...
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ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter V to AGND DD Analog Input Voltage to AGND MISCAL Reference Input ...
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ADE7761B PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 4. Pin Function Descriptions Pin No. Mnemonic Description 1 V Power Supply. This pin provides the supply voltage for the digital circuitry in the ADE7761B. The supply voltage DD should be maintained at ...
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Pin No. Mnemonic Description 15 FAULT This logic output goes active high when a fault or missing neutral condition occurs. A fault is defined as a condition under which the signals on V defined when the chip is powered up ...
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ADE7761B TYPICAL PERFORMANCE CHARACTERISTICS 1 ON-CHIP REFERENCE 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 0 CURRENT (% of Full Scale) Figure 4. Active Power Error As a Percentage of Reading with Gain ...
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TEST CIRCUIT 40A TO 80mA 18Ω 1MΩ 220V 1kΩ 33nF 10µF 100nF 1kΩ 33nF ADE7761B F1 REVP 1kΩ FAULT RB 33nF RCLKIN ...
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ADE7761B TERMINOLOGY Measurement Error The error associated with the energy measurement made by the ADE7761B is defined by = Percentage Error ⎛ Energy Registered by ADE7761B ⎜ ⎜ True Energy ⎝ Phase Error Between Channels The high-pass filter (HPF) in ...
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THEORY OF OPERATION POWER SUPPLY MONITOR The ADE7761B continuously monitors the power supply (V with its on-chip power supply monitor. If the supply is less than 4 V ± 5%, the ADE7761B goes into an inactive state; that is, no ...
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ADE7761B Typical Connection Diagrams Figure 15 shows a typical connection diagram for Channel V1. The analog inputs are used to monitor both the phase and neutral currents. Because of the large potential difference between the phase and neutral, two current ...
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ANALOG-TO-DIGITAL CONVERSION The analog-to-digital conversion in the ADE7761B is carried out using second-order, Σ-Δ ADCs. Figure 19 shows a first- order, Σ-Δ ADC (for simplicity). The converter is made up of two parts: the Σ-Δ modulator and the digital low-pass ...
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ADE7761B ACTIVE POWER CALCULATION The ADCs digitize the voltage signals from the current and voltage transducers. A high-pass filter in the current channel removes any dc component from the current signal. This eliminates any inaccuracies in the active power calculation ...
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sin ≠ where: i(t) is the instantaneous current the dc component the rms ...
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ADE7761B DIGITAL-TO-FREQUENCY CONVERSION As described in the Active Power Calculation section, the digital output of the low-pass filter after multiplication contains the active power information. However, because this LPF is not an ideal brick wall filter implementation, the output signal ...
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Table 6. f Frequency Selection 1– (Hz) 1– 13.7 1 Values are generated using the nominal frequency of 450 kHz are a binary ...
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ADE7761B Fault with Active Input Greater Than Inactive Input the active current input (that is, being used for billing), 1A and the voltage signal on V (inactive input) falls below 93.75 the fault ...
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244V rms POWER GENERATOR RB CT LOAD RF. Figure 31. Missing Neutral System Diagram The ADE7761B detects a missing neutral condition by continu- ously monitoring the ...
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ADE7761B Missing Neutral Gain Calibration When the ADE7761B is in missing neutral mode, the energy is billed based on the active current input signal level. The frequency outputs in this mode can be calibrated with the MISCAL analog input pin. ...
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APPLICATIONS INFORMATION INTERFACING TO A MICROCONTROLLER FOR ENERGY MEASUREMENT The easiest way to interface the ADE7761B to a microcontroller is to use the CF high frequency output with the output frequency scaling set to 2048 × ...
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ADE7761B Frequency Outputs Figure timing diagram for the various frequency outputs. The high frequency CF output is intended for communication and calibration purposes. CF produces wide, active high pulse ( frequency ...
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... OUTLINE DIMENSIONS 2.00 MAX 0.05 MIN COPLANARITY 0.10 ORDERING GUIDE Model Temperature Range ADE7761BARS –40°C to +85°C ADE7761BARS-RL –40°C to +85°C 1 ADE7761BARSZ –40°C to +85°C 1 ADE7761BARSZ-RL –40°C to +85°C ADE7761BARS-REF RoHS Compliant Part. 7.50 7.20 6. 5.60 5.30 8.20 5.00 7.80 7. 1.85 1.75 1.65 8° 0.38 SEATING 4° 0.22 PLANE 0° ...
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ADE7761B NOTES ©2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D06797-0-8/07(0) Rev Page ...