AD737-EVALZ Analog Devices Inc, AD737-EVALZ Datasheet
AD737-EVALZ
Specifications of AD737-EVALZ
Related parts for AD737-EVALZ
AD737-EVALZ 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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... Signal Range 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 Typ 0.2/0.3 0.4/0.5 0.2/0.2 −1.2 ±2.0 −1.2 0.5/0.7 0.007 0.007 ...
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... S 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 Typ ±0.9 ±0.9 ±2.7 ±4.0 ±4.0 1012 1012 300 1 ±1.7 ±1.7 ±3.8 ±3.8 ±11 ±11 6 ...
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... V and 0 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 Typ 5 ...
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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, 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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... Figure 2. SOIC_N Pin Configuration (R-8) 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, where ± unless 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 SUPPLY VOLTAGE (±V) Figure 6. Maximum Input Level vs. Supply Voltage ...
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... Figure 16. RMS Input Level vs. Frequency for Specified Averaging Error 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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... C tional filtering stage reduces any output ripple that was not removed by the averaging capacitor. Finally, the bias subsection permits a power-down function. This reduces the idle current of the AD737 from 160 μ μA. This feature is selected by connecting Pin 3 to Pin 7 (+V S ...
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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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... R3 and R4 provide current to offset the output Scaling the Output Voltage The output voltage can be scaled to the input rms voltage. For example, assume that the AD737 is retrofitted to an existing application using an averaging responding circuit (full-wave rectifier). The power supply the input voltage ac, and the desired output ...
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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% INPU ...
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... Figure 32. DC-Coupled Offset Voltage and Scale Factor Trims Rev Page 1kΩ 12 3500PPM/° 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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... AD737 AD737 EVALUATION BOARD An evaluation board, AD737-EVALZ, is available for experi- ments or for becoming familiar with rms-to-dc converters. Figure photograph of the board; Figure 35 to Figure 38 show the signal and power plane copper patterns. The board is designed for multipurpose applications and can be used for the AD736 as well. Although not shipped with the board, an optional socket that accepts the 8 ...
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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 BNC, right angle ...
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... AD737 OUTLINE DIMENSIONS COPLANARITY 5.00 (0.1968) 4.80 (0.1890 6.20 (0.2441) 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) 8° 0.10 (0.0040) 0° 0.51 (0.0201) 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 ...
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... Figure 42. 8-Lead Plastic Dual-In-Line Package [PDIP] (N-8) Dimensions shown in inches and (millimeters) Rev Page 0.325 (8.26) 0.310 (7.87) 0.300 (7.62) 0.060 (1.52) 0.195 (4.95) MAX 0.130 (3.30) 0.115 (2.92) GAUGE 0.014 (0.36) PLANE 0.010 (0.25) 0.008 (0.20) 0.430 (10.92) MAX AD737 ...
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... AD737KRZ-RL 0°C to 70°C 1 AD737KRZ-R7 0°C to 70°C 1 AD737-EVALZ RoHS Compliant Part. Package Description 8-Lead Plastic Dual In-Line Package [PDIP] 8-Lead Plastic Dual In-Line Package [PDIP] 8-Lead Ceramic Dual In-Line Package [CERDIP] 8-Lead Standard Small Outline Package [SOIC_N] ...
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... NOTES Rev Page AD737 ...
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... AD737 NOTES ©2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D00828-0-10/08(H) Rev Page ...