AD737 Analog Devices, AD737 Datasheet
AD737
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AD737 Summary of contents
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... Compared to these circuits, the AD737 offers higher accuracy at equal or lower cost. The AD737 can compute the rms value of both ac and dc input voltages. It can also be operated ac-coupled by adding one external capacitor. In this mode, the AD737 can resolve input signal levels of 100 μ ...
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... Reorganized Theory of Operation Section ................................. 12 Reorganized Applications Section................................................ 14 Added Scaling Input and Output Voltages Section.................... 14 Deleted Application Circuits Heading......................................... 16 Changes to Figure 28...................................................................... 16 Added AD737 Evaluation Board Section.................................... 18 Updated Outline Dimensions ....................................................... 20 Changes to Ordering Guide .......................................................... 21 1/05—Rev Rev. F Updated Format..................................................................Universal Added Functional Block Diagram.................................................. 1 Changes to General Description Section ...
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... Continuous ± RMS Level ±V = +2.8 V/−3 ±V = ± ±16 μ μ kHz, sine wave input applied to Pin 2, unless otherwise specified AD737A, AD737J AD737B, AD737K Min Typ Max Min 0.2/0.3 0.4/0.5 −1.2 ±2.0 0.5/0.7 0.007 0.014 0 −0.18 −0.3 ...
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... Pin 1 Output DC Resistance FREQUENCY RESPONSE High-Z Input (Pin 2) 1% Additional rms IN Error rms 100 mV rms 200 mV rms IN AD737A, AD737J AD737B, AD737K Min Typ Max Min ±0.9 ±2.7 ±4.0 1012 1 25 300 1 ±1.7 ±3.8 ±11 6.4 8 9.6 6.4 ±12 ± ...
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... Crest factor error is specified as the additional error resulting from the specific crest factor, using a 200 mV rms signal as a reference. The crest factor is defined rms. PEAK 5 DC offset does not limit ac resolution. AD737A, AD737J AD737B, AD737K Min Typ Max Min 5 55 ...
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... AD737 ABSOLUTE MAXIMUM RATINGS Table 2. Parameter Supply Voltage Internal Power Dissipation Input Voltage Output Short-Circuit Duration Differential Input Voltage Storage Temperature Range CERDIP (Q-8) PDIP (N-8) and SOIC_N (R-8) Lead Temperature Range, Soldering (60 sec) ESD Rating Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only ...
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... Table 4. Pin Function Descriptions Pin No. Mnemonic Description 1 C Coupling Capacitor for Indirect DC Coupling RMS Input POWER DOWN Disables the AD737. Low is enabled; high is powered down. 4 –V Negative Power Supply Averaging Capacitor OUTPUT Output Positive Power Supply. ...
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... AD737 TYPICAL PERFORMANCE CHARACTERISTICS T = 25°C, ±V = ±5 V (except AD737J-5, ± otherwise specified. 0 200mV rms 100µ 22µF F 0.3 0.1 0 –0.1 –0.3 –0 SUPPLY VOLTAGE (±V) Figure 5. Additional Error vs. Supply Voltage 16 DC COUPLED PIN ...
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... Rev Page 22µ 47µ 4.7µF F 100mV 1V INPUT LEVEL (rms 200mV rms 47µ 47µF F –0.5% –1% 100 FREQUENCY (Hz) for Specified Averaging Error –0.5% –1% AC COUPLED C = 10µ 47µ 100 FREQUENCY (Hz) AD737 47µF, 1k ...
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... AD737 4.0 3.5 3.0 2.5 2.0 1.5 1 SUPPLY VOLTAGE (±V) Figure 17. Input Bias Current vs. Supply Voltage 1V 100mV C = 10µF AV 10mV C = 33µF AV 1mV 100µV 1ms 10ms 100ms 1s SETTLING TIME Figure 18. RMS Input Level vs. Settling Time for Three Values 22µ 0µF ...
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... Figure 22. Additional Error vs. Crest Factor for Various Values of C 1.0 0.5 0 –0.5 –1.0 –1.5 –2.0 –2.5 100 1000 10mV 33µ 220µ Rev Page 22µ ±2. 47µ 4.7µ 100mV INPUT LEVEL (rms) Figure 23. Error vs. RMS Input Level Driving Pin 1 AD737 1V 2V ...
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... Finally, the bias subsection permits a power-down function. This reduces the idle current of the AD737 from 160 μ mere 30 μA. This feature is selected by connecting Pin 3 to Pin 7 (+V ...
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... SCR waveforms, have high crest factors. These – E (IDEAL) types of waveforms require a long averaging time constant to O average out the long time periods between pulses. Figure 10 shows the additional error vs. the crest factor of the AD737 for = various values of C CALCULATING SETTLING TIME ...
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... For low supply voltage applications, the maximum peak voltage to the device is extended by simply applying the input voltage to Pin 1 across the internal 8 kΩ input resistor. The AD737 input circuit functions quasi differentially, with a high impedance, FET input at Pin 2 (noninverting) and a low impedance input at Pin 1 (inverting, see Figure 26). The internal 8 kΩ ...
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... A Select the closest-value standard 1% resistor, 47.5 kΩ. Since the supply the common-mode voltage at the divider R7/ and the combined resistor value (R3 + R4) is equal to the feedback resistor, or 47.5 kΩ. Table 6. AD737 Capacitor Selection Application RMS Input Level General-Purpose RMS Computation ...
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... AD737 SWITCH CLOSED ACTIVATES POWER-DOWN MODE. AD737 DRAWS JUST 40µA IN THIS MODE 1PRV 0.01µF V 200mV IN 1N4148 9MΩ 2V 900kΩ 47kΩ 20V 1W 1N4148 90kΩ 200V POWER 10kΩ 1µF + INPUT SCALE FACTOR ADJ 69.8kΩ 5kΩ 0.47µF 1% INPUT C2 0.01µ CONNECT Figure 28 ...
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... NC 8 60.4Ω SCALE FACTOR + TRIM OUTPUT 6 2 AD711 REF –V S 1kΩ COM 499Ω AD737 8 1kΩ SCALE FULL-WAVE FACTOR RECTIFIER ADJUST + OUT AD737 PRECISION RESISTOR CORP TYPE PT/ST 2kΩ 31.6kΩ dB OUTPUT 100mV/dB ...
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... The board is tested prior to shipment and only requires a power supply connection and a precision meter, to perform measurements. Table 7 provides a bill of materials for the AD737 evaluation board. Figure 34. AD737 Evaluation Board—Component-Side Copper Figure 35. AD737 Evaluation Board—Secondary-Side Copper Figure 36. AD737 Evaluation Board— ...
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... Table 7. AD737 Evaluation Board Bill of Materials Qty Name Description 1 Test Loop Red 1 Test Loop Green 2 Capacitor Tantalum 10 μ Capacitor 0.1 μ 0603, X7R 1 Capacitor Tantalum 33 μF, 16V, 20%, 6032 5 Test Loop Purple 1 Integrated Circuit RMS-to-DC converter 4 Test Loop Black 2 Connector ...
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... AD737 OUTLINE DIMENSIONS 5.00 (0.1968) 4.80 (0.1890 6.20 (0.2440) 4.00 (0.1574) 1 5.80 (0.2284) 3.80 (0.1497) 4 1.27 (0.0500) BSC 1.75 (0.0688) 1.35 (0.0532) 0.25 (0.0098) 0.10 (0.0040) 0.51 (0.0201) COPLANARITY 0.10 0.31 (0.0122) 0.25 (0.0098) SEATING 0.17 (0.0067) PLANE COMPLIANT TO JEDEC STANDARDS MS-012-A A CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. ...
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... AD737JRZ-RL 0°C to 70°C 1 AD737JRZ-5 0°C to 70°C AD737JRZ-5-R7 1 0°C to 70°C 1 AD737JRZ-5-RL 0°C to 70°C AD737KN 0°C to 70°C 1 AD737KNZ 0°C to 70°C AD737KR 0°C to 70°C AD737KR-REEL 0°C to 70°C AD737KR-REEL7 0°C to 70°C 1 AD737KRZ 0° ...
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... AD737 NOTES Rev Page ...
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... NOTES Rev Page AD737 ...
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... AD737 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C00828-0-12/06(G) Rev Page ...