ade7762 Analog Devices, Inc., ade7762 Datasheet
ade7762
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ade7762 Summary of contents
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... V pin. The ADE7762 remains inactive until the supply voltage reaches the supply falls below 4 V, the ADE7762 DD resets and no pulses are issued on F1, F2, and CF. A multiple multiplexed logic output provides phase dropout per phase, reverse polarity per phase, and a phase sequence error. ...
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... ADE7762 TABLE OF CONTENTS Features .............................................................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Functional Block Diagram .............................................................. 3 Specifications..................................................................................... 4 Timing Characteristics ................................................................ 5 Absolute Maximum Ratings............................................................ 6 ESD Caution.................................................................................. 6 Pin Configuration and Function Descriptions............................. 7 Typical Performance Characteristics ............................................. 9 Test Circuit ...................................................................................... 10 Terminology .................................................................................... 11 Theory of Operation ...................................................................... 12 Power Factor Considerations.................................................... 12 Nonsinusoidal Voltage and Current ........................................ 13 Analog Inputs.................................................................................. 14 Current Channels ...
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... PHASE AND REVP MONITOR LED_CTRL LED_A LED_B LED_C REVP IN/OUT Figure 1. Rev Page ABS POWER X LPF SUPPLY MONITOR ADE7762 X DGND 4 21 CLKIN CLKOUT 22 X DIGITAL-TO-FREQUENCY CONVERTER SCF ADE7762 ...
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... ADE7762 SPECIFICATIONS ± 5%, AGND = DGND = 0 V, on-chip reference, CLKIN = 10 MHz Table 1. Parameter 1, 2 ACCURACY Measurement Error on Current Channel Phase Error Between Channels PF = 0.8 Capacitive PF = 0.5 Capacitive AC Power Supply Rejection Output Frequency Variation (CF) DC Power Supply Rejection Output Frequency Variation (CF) ANALOG INPUTS ...
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... Figure 3. Timing Diagram for LED Drivers Rev Page Min Typ Max 4.75 5.25 8 −40°C to +85°C, unless otherwise noted. MIN MAX Value 120 See Figure 2 ½ See Table 7 4/CLKIN 28.8 57.5 7.2 ADE7762 Unit V mA Unit ms sec sec ms sec sec μs μs μs ...
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... ADE7762 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter V to AGND DGND DD Analog Input Voltage to AGND VAP, VBP, VCP, VN, IAP, IAN, IBP, IBN, ICP, and ICN Reference Input Voltage to AGND Digital Input Voltage to DGND Digital Output Voltage to DGND ...
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... V Power Supply. This pin provides the supply voltage for the digital circuitry in the ADE7762. The supply DD voltage should be maintained ± 5% for a specified operation. This pin should be decoupled to DGND with a 10 μF capacitor in parallel with a 100 nF ceramic capacitor. ...
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... CLKOUT A crystal can be connected across this pin and CLKIN as described for Pin 21 to provide a clock source for the ADE7762. The CLKOUT pin can drive one CMOS load when an external clock is supplied at CLKIN or when a crystal is used. 23, 24 S0, S1 These logic inputs are used to select one of four possible frequencies for the digital-to-frequency conversion for design flexibility ...
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... POWER FACTOR = 0 LINE FREQUENCY (Hz) Figure 9. Error As a Percent of Reading over Frequency with an Internal Reference (Wye Connection) 0.5 0.4 0.3 0.2 5V 4.75V 0.1 0 5.25V 0 CURRENT CHANNEL (% of Full Scale) Figure 10. Error As a Percent of Reading over Power Supply with Internal Reference (Wye Connection) ADE7762 100 65 100 ...
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... ADE7762 TEST CIRCUIT 1MΩ 220V 1kΩ 10µF 100nF LOAD ABS DD 1kΩ IAP 33nF ADE7762 Rb CF 1kΩ 3 IAN 8 33nF CLKOUT 22 IBP 9 SAME AS CLKIN 21 IAP, IAN 10 IBN S0 23 ICP SAME AS IAP, IAN SCF ICN REF ...
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... Gain Error The gain error of the ADE7762 is defined as the difference between the measured output frequency (minus the offset) and the ideal output frequency. The difference is expressed as a percentage of the ideal frequency. The ideal frequency is obtained from the ADE7762 transfer function (see the Transfer Function section) ...
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... MULTIPLIER VCP ADC VN The low frequency output of the ADE7762 is generated by accumulating the total active power information. This low frequency inherently means a long accumulation time between output pulses. The output frequency is therefore proportional to the average active power. This average active power information can, in turn, be accumulated (for example counter) to generate active energy information ...
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... A limiting α (3) n factor on harmonic measurement is the bandwidth. On the ADE7762, the bandwidth of the active power measurement is 14 kHz with a master clock frequency of 10 MHz. Rev Page ∞ ∑ ...
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... Voltage channels must be driven from a common-mode voltage, that is, the differential voltage signal on the input must be refer- enced to a common mode (usually AGND). The analog inputs of the ADE7762 can be driven with common-mode voltages with respect to AGND. However, best results are achieved using a common mode equal to AGND. ...
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... The first option uses a potential transformer (PT) to pro- vide complete isolation from the main voltage. In the second option, the ADE7762 is biased around the neutral wire, and a resistor divider is used to provide a voltage signal proportional to the line voltage. Adjusting the ratio of Ra, Rb, and convenient way of carrying out a gain calibration on the meter ...
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... Figure 18. 3-Phase, 3-Wire Meter Connection with ADE7762 Note that only two current inputs and two voltage inputs of the ADE7762 are used in this case. The active power calculated by the ADE7762 does not depend on the selected channels. Figure 19 shows the connections of the ADE7762 analog inputs with the power lines in a 3-phase, 4-wire Wye service ...
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... At power-up, DD when the supply is less than 4 V ± 2% and V (typical), the outputs of the ADE7762 are inactive and the data path is held in reset. Once VDD is greater than 4 V ±2% and VREF is greater than 1.9 V (typical), the chip is active and energy accumulation begins ...
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... PHASE SEQUENCE ERROR The ADE7762 detects the zero crossing of each phase. A phase sequence error occurs when the sequence A>B>C>A> … is violated phase sequence error occurs, the Phase Seq/Drop LEDs blink (see Figure 22) ...
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... CROSSINGS PHASE SEQ/DROP LEDS ARE BLINKING AT 1Hz. 80 0° +120° 20% FS VOLTAGE WAVEFORMS RISING EDGE ZERO CROSSINGS PHASE SEQ/DROP LED FOR PHASE B IS ON. Figure 22. Phase Sequence Detection Rev Page –120° ADE7762 ...
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... The HPF in the current channels has an associated phase response that is compensated for on-chip. Figure 24 and Figure 25 show the phase error between channels with the compensation network. The ADE7762 is phase compensated kHz as shown. This ensures correct active harmonic power calculation even at low power factors. ...
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... VC MULTIPLIER IC The average value of a sinusoidal signal is zero. Thus, the frequency generated by the ADE7762 is proportional to the average active power. Figure 26 shows the digital-to-frequency conversion for steady load conditions, that is, constant voltage and current. The frequency output CF varies over time, even under steady load conditions (see Figure 26). This frequency variation is primarily due to the cos(2ω ...
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... To remedy this, an appropriate integration time should be considered to achieve the desired accuracy. Mode Selection of the Sum of the Three Active Energies The ADE7762 can be configured to execute the arithmetic sum of the three active energies ΦA sum of the absolute value of these energies |Wh ...
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... The maximum frequency also depends on the number (12) of phases connected to the ADE7762 3-phase, 3-wire delta service, the maximum output frequency is different from the maxi- mum output frequency in a 3-phase, 4-wire Wye service. The ...
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... BN B ⎝ ⎠ ⎝ l ⎝ 3 where × sin(2π/ × sin(π/ the LPF on each channel eliminates the 2ω the equation, the active power measured by the ADE7762 × × + × × full-scale ac voltage of ± ...
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... As in the case of F1 and F2, if the period 190 ms, the CF pulse width is set to half the period. For exam- ple, if the CF frequency is 20 Hz, the CF pulse width is 25 ms. Rev Page ADE7762 frequency for a meter design, the (maximum load) with a 100 imp/kWh MAX ) ...
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... Current Phase A is 10% of full scale with this detection scheme detects that VA × below the no-load threshold but that VB × IA and VC × IA are not. Therefore, the ADE7762 does not detect a no-load threshold for V × I and lets this phase contribute to the total power ...
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... REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. Figure 27. 28-Lead Standard Small Outline Package [SOIC_W] Wide Body (RW-28) Dimensions shown in millimeters and (inches) Package Description 28-Lead Standard Small Outline Package [SOIC_W] 28-Lead [SOIC_W], 13” Reel ADE7762 Evaluation Board Rev Page 45° 8° 0° 1.27 (0.0500) 0.33 (0.0130) 0.40 (0.0157) ...
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... ADE7762 NOTES ©2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05757-0-8/07(0) Rev Page ...