ade7760 Analog Devices, Inc., ade7760 Datasheet
ade7760
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ade7760 Summary of contents
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... The part specifications surpass the accuracy require- ments as quoted in the IEC61036 standard. The only analog circuitry used on the ADE7760 is in the ADCs and reference circuit. All other signal processing (such as multi- plication and filtering) is carried out in the digital domain. This approach provides superior stability and accuracy over extremes in environmental conditions and over time ...
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... ADE7760 TABLE OF CONTENTS Specifications..................................................................................... 3 Timing Characteristics..................................................................... 5 Absolute Maximum Ratings............................................................ 6 ESD Caution.................................................................................. 6 Terminology ...................................................................................... 7 Pin Configuration and Function Descriptions............................. 8 Typical Performance Characteristics ........................................... 10 Operation......................................................................................... 11 Power Supply Monitor ............................................................... 11 Analog Inputs.............................................................................. 11 Internal Oscillator ...................................................................... 12 Analog-to-Digital Conversion.................................................. 12 REVISION HISTORY Revision 0: Initial Version Active Power Calculation .......................................................... 13 Digital-to-Frequency Conversion ............................................ 15 Transfer Function ...
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... V, min ± 0.8 V, max ± ±3 µA, max Typical 10 nA pF, max Rev Page ADE7760 = –40°C to +85° ±100 mV rms ±100 mV rms 2P active) 1B active – – ...
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... ADE7760 Parameter 4 LOGIC OUTPUTS CF, REVP, and FAULT Output High Voltage Output Low Voltage and F2 Output High Voltage Output Low Voltage POWER SUPPLY See plots in the Ty pical Performance Characteristics 2 See the Terminology section for explanation of specifications. ...
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... Time between F1 Falling Edge and F2 Falling Edge Pulse Width (Logic High Pulse Period. See the Transfer Function section. s Minimum Time between F1 and F2 Pulse Figure 2. Timing Diagram for Frequency Outputs Rev Page ADE7760 = –40°C to +85°C. MAX ...
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... ADE7760 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter V to AGND DD Analog Input Voltage to AGND 1AP 1BP Reference Input Voltage to AGND Digital Input Voltage to DGND Digital Output Voltage to DGND Operating Temperature Range Industrial Storage Temperature Range ...
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... HPFs are switched on, the offset is removed from the current channels and the power calculation is not affected by this offset. Gain Error The gain error in the ADE7760 ADCs is defined as the differ- ence between the measured output frequency (minus the offset) and the ideal output frequency. The difference is expressed as a percentage of the ideal frequency ...
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... AGND This pin provides the ground reference for the analog circuitry in the ADE7760, that is, ADCs and reference. This pin should be tied to the analog ground plane of the PCB. The analog ground plane is the ground reference for all analog circuitry such as antialiasing filters, and current and voltage transducers. ...
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... DGND This pin provides the ground reference for the digital circuitry in the ADE7760, that is, multiplier, filters, and digital-to-frequency converter. This pin should be tied to the digital ground plane of the PCB. The digital ground plane is the ground reference for all digital circuitry such as counters (mechanical and digital), MCUs, and indicator LEDs ...
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... PF = 0.5 100 100nF 33nF ADE7760 FAULT RB 33nF RCLKIN 33nF 33nF S1 SCF REF V 6 IN/OUT 2P INT AGND DGND Figure 7 ...
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... ADE7760 the supply is less than 4 V ± 5%, the ADE7760 goes into an inactive state, that is, no energy is accumulated and the CF, F1, and F2 outputs is disabled. This is useful to ensure correct device operation at power-up and during power-down. The power supply monitor has built-in hysteresis and filtering ...
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... A Σ-Δ modulator converts the input signal into a continuous serial stream of 1s and rate determined by the sampling clock. In the ADE7760, the sampling clock is equal to CLKIN. The 1-bit DAC in the feedback loop is driven by the serial data stream. The DAC output is subtracted from the input signal. If ...
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... All signal processing is carried out in the digital domain for superior stability over temperature and time. The low frequency output of the ADE7760 is generated by accumulating this active power information. This low frequency inherently means a long accumulation time between output pulses ...
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... LPF and used to generate the active power information, the offsets contribute a constant error to the active power calcula- (2) ) tion. This problem is easily avoided in the ADE7760 with the h HPF in Channel 1. By removing the offset from at least one channel, no error component can be generated the multiplication. Error terms at cos(ω ...
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... The HPF in Channel 1 has an associated phase response that is compensated for on-chip. Figure 20 and Figure 21 show the phase error between channels with the compensation network activated. The ADE7760 is phase compensated kHz as shown, which ensures correct active harmonic power calculation even at low power factors. ...
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... TRANSFER FUNCTION Frequency Outputs F1 and F2 The ADE7760 calculates the product of two voltage signals (on Channel 1 and Channel 2) and then low-pass filters this product to extract active power information. This active power information is then converted to a frequency. The frequency information is output on F1 and F2 in the form of active high pulses ...
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... important that both current 1A 1B transducers be closely matched. On power-up, the output pulse rate of the ADE7760 is pro- portional to the product of the voltage signals on V Channel 2. If there is a difference of greater than 6.25% between V and V on power-up, the fault indicator (FAULT) becomes ...
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... Figure 25. Fault Conditions for Inactive Input Greater than Active Input If the neutral circuit is chosen for the current circuit in the arrangement shown in Figure 25, this may have implications for the calibration accuracy. The ADE7760 powers up with the V input active as normal. However, because there is no current in the phase circuit, the signal on V ...
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... APPLICATIONS INTERFACING TO A MICROCONTROLLER FOR ENERGY MEASUREMENT The easiest way to interface the ADE7760 to a microcontroller is to use the CF high frequency output with the output fre- quency scaling set to 2048 × F1, F2. This is done by setting SCF = 0 and (see Table 7). With full-scale ac signals on the analog inputs, the output frequency approxi- mately 5 ...
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... No-Load Threshold The ADE7760 also includes a no-load threshold and startup current feature that eliminates any creep effects in the meter. The ADE7760 is designed to issue a minimum output frequency. Any load generating a frequency lower than this minimum frequency does not cause a pulse to be issued on F1, F2 ...
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... BSC 0.22 SEATING PLANE 0.10 COMPLIANT TO JEDEC STANDARDS MO-150AE Figure 27. 20-Lead Shrink Small Outline Package [SSOP] (RS-20) Dimensions shown in millimeters Package Description 20-Lead Shrink Small Outline Package [SSOP] 20-Lead Shrink Small Outline Package [SSOP] Rev Page 8° 0.95 4° 0.75 0° 0.55 Package Option RS-20 RS-20 ADE7760 ...
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... ADE7760 NOTES Rev Page ...
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... NOTES Rev Page ADE7760 ...
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... ADE7760 NOTES © 2004 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D04434–0–1/04(0) Rev Page ...