AD7751AAN Analog Devices, AD7751AAN Datasheet
AD7751AAN
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AD7751AAN Summary of contents
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GENERAL DESCRIPTION The AD7751 is a high-accuracy fault-tolerant electrical energy measurement IC that is intended for use with 2-wire distribution systems. The part specifications surpass the accuracy require- ments as quoted in the IEC1036 standard. V1A V1N V1B V2P ...
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AD7751–SPECIFICATIONS Parameter 3 ACCURACY 1 Measurement Error on Channels 1 and 2 Gain = 1 Gain = 2 Gain = 8 Gain = 16 1 Phase Error Between Channels V1 Phase Lead 37° (PF = 0.8 Capacitive) V1 Phase Lag ...
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... V max max 2.5 2.5 mA max ( 5%, AGND = DGND = 0 V, On-Chip Reference, CLKIN = 3.58 MHz – +85 C) MIN MAX Unit ms sec sec ms sec sec Model AD7751AAN AD7751AARS AD7751ABRS EVAL-AD7751EB AD7751AAN-REF Test Conditions/Comments SOURCE SINK SOURCE SINK For Specified Performance 5 V – – Typically 2 mA Typically 1 ...
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AD7751 ABSOLUTE MAXIMUM RATINGS (T = 25°C unless otherwise noted AGND . . . . . . . . . . . . . . . . . . . . . . . –0 ...
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Pin No. Mnemonic Description 1 DV Digital Power Supply. This pin provides the supply voltage for the digital circuitry in the AD7751. DD The supply voltage should be maintained ± 5% for specified operation. This pin should ...
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AD7751 Pin No. Mnemonic Description 20 REVP This logic output will go logic high when negative power is detected, i.e., when the phase angle between the voltage and current signals is greater that 90°. This output is not latched and ...
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0.40 GAIN = 1 ON-CHIP REFERENCE 0. 0.20 0.10 –40 C 0.00 –0. –0.20 –0.30 –0.40 –0.50 0.01 0.10 1.00 10.0 AMPS 0. GAIN = 2 ON-CHIP REFERENCE 0.20 ...
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AD7751 0.20 +25 C PF=1 0.10 0.00 +85 C PF=0.5 –0.10 –0.20 +25 C PF=0.5 –0.30 –0.40 –0. 0.5 GAIN = 8 ON-CHIP REFERENCE –0.60 0.01 0.1 1 AMPS 0. 0.5 GAIN = 16 0.40 ON-CHIP ...
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DISTRIBUTION CHARACTERISTICS 16 NUMBER OF PTS: 138 MINIMUM: –11.1367 MAXIMUM: 10.1775 14 MEAN: –1.44576 STD DEV: 4.6670 12 GAIN = 1 TEMP = DISTRIBUTION CHARACTERISTICS NUMBER ...
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AD7751 THEORY OF OPERATION The two ADCs digitize the voltage and current signals from the current and voltage transducers. These ADCs are 16-bit second order sigma-delta converters with an oversampling rate of 900 kHz. This analog input structure greatly simplifies ...
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Using Equations 2 and 3, the real-power P can be expressed in terms of its fundamental real power (P power ( where: = × φ cos ...
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AD7751 Figure 7 shows two typical connections for Channel V2. The first option uses a PT (Potential Transformer) to provide com- plete isolation from the mains voltage. In the second option the AD7751 is biased around the neutral wire and ...
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FREQUENCY – Hz DIGITAL-TO-FREQUENCY CONVERSION As previously described, the digital output of the low-pass filter after multiplication contains the real-power information. However, since this LPF is not ...
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AD7751 Fault with Active Input Greater than Inactive Input If V1A is the active current input (i.e., is being used for billing), and the signal on V1B (inactive input) falls by more than 12.5% of V1A, the fault indicator will ...
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Output frequency on F1 and F2 (Hz) Freq = Differential rms voltage signal on Channel 1 (volts Differential rms voltage signal on Channel 2 (volts) V2 Gain = 16, depending on the ...
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AD7751 The F frequencies allow complete coverage of this range of 1–4 output frequencies on F1 and F2. When designing an energy meter, the nominal design voltage on Channel 2 (voltage) should be set to half-scale to allow for calibration ...