AD637 Analog Devices, AD637 Datasheet
AD637
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AD637 Summary of contents
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... The inputs are not damaged by input signals if the supply voltages are lost. The AD637 is available in accuracy Grade J and Grade K for commercial temperature range (0°C to 70°C) applications, accuracy Grade A and Grade B for industrial range (−40°C to +85°C) appli- cations, and accuracy Grade S rated over the − ...
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... AD637 TABLE OF CONTENTS Features .............................................................................................. 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 5 ESD Caution.................................................................................. 5 Pin Configurations and Function Descriptions ........................... 6 Functional Description .................................................................... 7 Standard Connection ................................................................... 8 Chip Select..................................................................................... 8 Optional Trims for High Accuracy ............................................ 8 REVISION HISTORY 4/07—Rev Rev. J Added Evaluation Board Section ................................................. 16 Updated Outline Dimensions ....................................................... 20 10/06— ...
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... Specified accuracy ±0.1 ±1 ±15 ± ±6 ±6 ±15 ±15 9.6 6.4 8 9.6 ±0.2 ±0 200 150 1 8 AD637 Unit mV ±% of reading mV ± reading μV/V μV reading % of FSR % of FSR mV ± reading % of reading % of reading ms/μ rms V p-p V rms V p-p V p-p kΩ ...
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... All minimum and maximum specifications are guaranteed, although only those shown in boldface are tested on all production units. 2 Accuracy specified 0 V rms rms dc with AD637 connected, as shown in Figure 5. 3 Nonlinearity is defined as the maximum deviation from the straight line connecting the readings and 2 V. ...
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... Storage Temperature Range Lead Temperature (Soldering 10 sec) Rated Operating Temperature Range AD637J, AD637K AD637A, AD637B AD637S, 5962-8963701CA Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress Rating rating only; functional operation of the device at these or any ...
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... Rev Page BUFF IN BUFF OUT COMMON AD637 OUTPUT OFFSET + TOP VIEW S (Not to Scale) CS – DEN INPUT RMS OUT OUTPUT CONNECT Figure 3 ...
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... ABSOLUTE VALUE VOLTAGE TO CURRENT CONVERTER 6kΩ 12kΩ The AD637 embodies an implicit solution of the rms equation that overcomes the inherent limitations of straightforward rms computation. The actual computation performed by the AD637 follows the equation ⎡ ⎤ ⎢ ...
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... Figure 6. The output signal can be used buffered or nonbuffered, depending on the characteristics of the load buffer is needed, tie the buffer input (Pin 1) to common. The output of the AD637 is capable of driving 5 mA into a 2 kΩ load without degrading the accuracy of the device. BUFF ...
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... AV Figure 10. Comparison of Percent DC Error to the Percent Peak Ripple over Frequency Using the AD637 in the Standard RMS Connection with a 1 × μF C The ac ripple component of averaging error is greatly reduced by increasing the value of the averaging capacitor. There are two major disadvantages to this: the value of the averaging capacitor ...
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... AD637 AD637 1 BUFF ABSOLUTE VALUE 3 COMMON SQUARER/ OUTPUT DIVIDER 4 OFFSET BIAS +V 4.7kΩ 25kΩ DEN 25kΩ 6 INPUT 7 dB OUTPUT RX 24kΩ Figure 11. 2-Pole Sallen-Key Filter Figure 12 shows values of C and the corresponding averaging AV error as a function of sine wave frequency for the standard rms connection ...
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... To ensure that the input signal is accurately presented to the converter, the input buffer must have a −3 dB bandwidth that is wider than that of the AD637. Note the importance of slew rate in this application. For example, the minimum slew rate required for rms, 5 MHz, sine wave input signal is 44 V/μs. The user is ...
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... PULSE WIDTH (µs) Figure 17. AD637 Error vs. Pulse Width Rectangular Pulse Figure curve of additional reading error for the AD637 for rms input signal with crest factors from 1 to 11. A rectangular pulse train (pulse width 100 μs) is used for this test because it is the worst-case waveform for rms measurement (all the energy is contained in the peaks) ...
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... S 25kΩ FILTER CONNECT +V S AD508J Figure 20. dB Connection Rev Page SCALE FACTOR 33.2kΩ ADJUST 5kΩ 1kΩ 60.4Ω AD707JN 6 COMPENSATED OUTPUT + 100mV/dB – – OUT 1µF AD637 ...
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... The output of the circuit AV1 This concept can be expanded to include additional terms by feeding the signal from Pin 9 of each additional AD637 through a 10 kΩ resistor to the summing junction of the tying all of the denominator inputs (Pin 6) together ...
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... S S 25kΩ 10 –V – OUT 9 100pF 5pF 10kΩ 10kΩ BUFF OUT AD711K Y 13 10kΩ 20kΩ 25kΩ 10 –V – OUT 9 100pF OUT X Y AD637 ...
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... AD637 EVALUATION BOARD The evaluation board for the AD637 is shown in Figure 23 available at www.analog.com and ships fully tested and ready for bench testing by just adding power and signal connections. The circuit is configured for dual power supplies, and standard BNC connectors serve as the signal input and output ports. ...
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... Figure 26. Evaluation Board—Secondary Side Copper Figure 27. Evaluation Board—Internal Power Plane Figure 28. Evaluaiton Board—Internal Ground Plane Rev Page AD637 ...
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... F931E106MCC Kemet C0603C104K4RACTU Nichicon F931C226MCC AMP 227161-1 Components Corp. TP-104-01-00 Panasonic ERJ-3EKF1004V Bourns 3361S-1-503G Panasonic ERJ-3EKF4751V Molex 22-10-2021 Analog Devices, Inc. AD637ARZ BUF OUT (VIO TEST LOOP) CIN 22µF 16V RMS IN RMS 0.1µF DC OUT –V (VIO TEST + S C4 LOOP) 0.1µ ...
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... PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. Figure 31. 14-Lead Ceramic Dual In-Line Package [CERDIP] (Q-14) Dimensions shown in inches and (millimeters) Rev Page 0.320 (8.13) 0.290 (7.37) 0.015 (0.38) 0.008 (0.20) 0.320 (8.13) 0.290 (7.37) 0.015 (0.38) 15° 0.008 (0.20) 0° AD637 ...
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... AD637JR-REEL7 0°C to 70°C AD637JRZ 0°C to 70°C AD637JRZ-RL 0°C to 70°C AD637JRZ-R7 0°C to 70°C AD637KD 0°C to 70°C AD637KDZ 0°C to 70°C AD637KQ 0°C to 70°C AD637KR 0°C to 70°C AD637KRZ 0°C to 70°C AD637SD −55°C to +125°C AD637SD/883B − ...