AD7755AAN Analog Devices Inc, AD7755AAN Datasheet
AD7755AAN
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AD7755AAN Summary of contents
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G0 V1P V1N x1, x2, x8, x16 V2P V2N REFERENCE U.S. Patents 5,745,323, 5,760,617, 5,862,069, 5,872,469. GENERAL DESCRIPTION The AD7755 is a high accuracy electrical energy measurement IC. The part specifications surpass the accuracy requirements as quoted in the ...
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AD7755–SPECIFICATIONS Parameter 1, 2 ACCURACY 1 Measurement Error on Channel 1 Gain = 1 Gain = 2 Gain = 8 Gain = 16 1 Phase Error Between Channels V1 Phase Lead 37 (PF = 0.8 Capacitive) V1 Phase Lag 60 ...
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... The CF pulse is always the high frequency mode. See Frequency Outputs section and Table IV. Specifications subject to change without notice Model AD7755AAN AD7755AARS AD7755ABRS EVAL-AD7755EB AD7755 Evaluation Board AD7755AAN-REF AD7755 Reference Design PCB (See AN-559) A Version B Version Unit 4.75 4.75 V min 5.25 5.25 V max 4.75 4.75 V min 5 ...
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AD7755 ABSOLUTE MAXIMUM RATINGS (T = +25 C unless otherwise noted AGND . . . . . . . . . . . . . . . . . . . . . . . –0.3 V ...
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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 AD7755. DD The supply voltage should be maintained decoupled with capacitor in parallel ...
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AD7755 Pin No. Mnemonic Description 21 DGND This provides the ground reference for the digital circuitry in the AD7755, i.e., multiplier, filters and digital-to-frequency converter. This pin should be tied to the analog ground plane of the PCB. The digital ...
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C 0.4 0.3 0.2 0.1 +25 C 0.0 –0.1 +85 C –0.2 –0 GAIN = 1 –0.4 ON-CHIP REFERENCE –0.5 10 0.01 0.1 1 Amps 0.5 –40 C 0.4 0.3 0.2 0.1 +25 C 0.0 ...
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AD7755 0.8 0.6 – 0.5 0.4 0.2 + 0.0 + 0.5 –0.2 –0.4 + 0.5 –0.6 –0.8 0.01 0.1 1 Amps 0.4 – 0.5 ...
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DISTRIBUTION CHARACTERISTICS NUMBER POINTS: 101 14 MINIMUM: –9.78871 GAIN = 1 MAXIMUM: 7.2939 TEMPERATURE = +25 C MEAN: –1.73203 12 STD. DEV: 3.61157 –15 –9 –3 3 FREQUENCY – GAIN = ...
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AD7755 THEORY OF OPERATION The two ADCs digitize the voltage signals from the current and voltage transducers. These ADCs are 16-bit second order sigma-delta with an oversampling rate of 900 kHz. This analog input structure greatly simplifies transducer interfacing by ...
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Using Equations 1 and 2, the real power P can be expressed in terms of its fundamental real power (P power ( where cos – 1 ...
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AD7755 Figure 25 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 AD7755 is biased around the neutral wire, and ...
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FREQUENCY – Hz 0.30 0.25 0.20 0.15 0.10 0.05 0 –0.05 –0. FREQUENCY – Hz DIGITAL-TO-FREQUENCY CONVERSION As previously described, ...
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AD7755 Interfacing the AD7755 to a Microcontroller for Energy Measurement The easiest way to interface the AD7755 to a microcontroller is to use the CF high frequency output with the output frequency scaling set to 2048 F1, F2. This is ...
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Example 1 Thus if full-scale differential dc voltages of +470 mV and –660 mV are applied to V1 and V2 respectively (470 mV is the maximum differential voltage that can be connected to Channel 1 and 660 mV is the ...
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AD7755 Table VI. F1 and F2 Frequency with Half-Scale AC Inputs Frequency on F1 and F2– CH1 and CH2 Half-Scale AC Inputs 1– 1.7 0.085 3.4 0. 6.8 0.34 ...