AD627 Analog Devices, AD627 Datasheet
AD627
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AD627 Summary of contents
Page 1
... With no external resistor, the AD627 is configured for a gain of 5. With an external resistor, it can be set to a gain 1000. A wide supply voltage range (+2 ±18 V) and micropower current consumption make the AD627 a perfect fit for a wide range of applications ...
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... Dual Supply ................................................................................... 5 Dual and Single Supplies ............................................................. 6 Absolute Maximum Ratings............................................................ 7 ESD Caution.................................................................................. 7 Pin Configurations and Function Descriptions ........................... 8 Typical Performance Characteristics ............................................. 9 Theory of Operation ...................................................................... 14 Using the AD627 ............................................................................ 15 Basic Connections ...................................................................... 15 Setting the Gain .......................................................................... 15 REVISION HISTORY 11/07—Rev Rev. D Changes to Features.......................................................................... 1 Changes to Figure 29 to Figure 34 Captions ............................... 13 Changes to Setting the Gain Section ...
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... (+V ) − 70 (− (+V ) − (+V ) − 25 (− (+V ) − ±25 AD627 Unit V ppm ppm ppm/°C ppm/°C μV μV μV/°C μV μV μV/° pA/° pA/°C GΩ||pF GΩ ...
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... G = +100 Overload Recovery 50% input overload 1 Does not include effects of External Resistor See Table 8 for total RTI errors. 3 See the Using the AD627 section for more information on the input range, gain range, and common-mode range. AD627A Min Typ 80 3 0.4 +0.05/−0.07 65 290 ...
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... (+V ) − 70 (− (+ (+V ) − 25 (− (+ ±25 AD627 Unit V ppm ppm ppm/°C ppm/°C μV μV μV/°C μV μV μV/° pA/° pA/°C GΩ||pF GΩ||pF ) − ...
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... POWER SUPPLY Operating Range Dual supply Single supply Quiescent Current Over Temperature TEMPERATURE RANGE For Specified Performance 1 See Using the AD627 section for more information on the reference terminal, input range, gain range, and common-mode range. AD627A Min Typ 80 3 0.4 +0.05/−0.06 135 ...
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... W device reliability. −V − −V − − (−V ) ESD CAUTION S S Indefinite −65°C to +125°C −40°C to +85°C 300°C Rev Page AD627 ...
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... Output Voltage Positive Supply Voltage External Gain Setting Resistor. Place gain setting resistor across Rev Page AD627 +V – TOP VIEW OUTPUT + (Not to Scale) –V REF Figure 4. 8-Lead SOIC_N Pin Configuration pins to set the gain ...
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... TOTAL POWER SUPPLY VOLTAGE (V) Figure 9. Supply Current vs. Supply Voltage ±15V ±1. ± ±2.5V S SOURCING SINKING V = ± ±2. ±1. ±15V S V– OUTPUT CURRENT (mA) Figure 10. Output Voltage Swing vs. Output Current AD627 120 140 ...
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... AD627 500mV 100 10 Figure 11. 0 Current Noise (0.71 pA/DIV) 20mV 100 10 Figure 12. 0 RTI Voltage Noise (400 nV/DIV 100 10 Figure 13. 0 RTI Voltage Noise (200 nV/DIV +1000 120 110 1s 100 100 1s 1s 120 1s 110 100 Rev Page ...
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... Figure 22. Large Signal Pulse Response and Settling Time –1000, Rev Page ±2 ±4 ±6 ±8 OUTPUT PULSE ( 100 pF L 200µV 1V 100µ kΩ 100 pF (100 μV = 0.01 200µV 1V 500µ kΩ 100 pF (10 μV = 0.01 AD627 ± kΩ, L ...
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... AD627 120 110 100 100 1k FREQUENCY (Hz) Figure 23. CMRR vs. Frequency, ± +1000 +100 + –10 –20 –30 100 1k 10k FREQUENCY (Hz) Figure 24. Gain vs. Frequency ( V 20µs CH2 20mV Figure 25 ...
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... Figure 32. Gain Nonlinearity, Negative Input ± +100 (7 ppm/DIV) S 200µV/DIV Figure 33. Gain Nonlinearity, Negative Input ± ppm/DIV) S 200µV/DIV Figure 34. Gain Nonlinearity, Negative Input ± +100 (7 ppm/DIV) S Rev Page AD627 V OUT 3V/DIV V OUT 3V/DIV V OUT 3V/DIV ...
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... The AD627 is a true instrumentation amplifier, built using two feedback loops. Its general properties are similar to those of the classic two-op-amp instrumentation amplifier configuration but internally the details are somewhat different. The AD627 uses a modified current feedback scheme, which, coupled with interstage feedforward frequency compensation, results in a much better ...
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... This results in a gain that is always slightly less than the desired gain, thereby preventing clipping of the signal at the output due to resistor tolerance. The internal resistors on the AD627 have a negative temperature coefficient of −75 ppm/°C maximum for gains > 5. Using a gain resistor that also has a negative temperature coefficient of − ...
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... It is clear, 6.00 from either Equation 3 or Equation 4, that an increasing V 7.00 (while it acts as a positive offset at the output of the AD627) 7.94 tends to decrease the voltage on A1. Figure 38 and Figure 39 8.91 show the maximum voltages that can be applied to the REF pin 9 ...
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... V (the exception is an input range V). OUTPUT BUFFERING The AD627 is designed to drive loads of 20 kΩ or greater but can deliver heavier loads at lower output voltage swings (see Figure 10). If more than output current is required at the output, buffer the AD627 output with a precision op amp, such as the OP113 ...
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... A ±100 mV signal from a resistive bridge (common-mode voltage = 2 amplified. This example compares the resulting errors from a discrete two-op-amp instrumentation amplifier and the AD627. The discrete implementation uses a four-resistor precision network (1% match, 50 ppm/°C tracking). +5V 350Ω ...
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... To put this in context, a 12-bit data acquisition system, with an input range 2.5 V, has an LSB weighting of 610 μV. By contrast, the AD627 uses precision laser trimming of internal resistors, along with patented CMR trimming, to yield a higher dc CMRR and a wider bandwidth over which the CMRR is flat (see Figure 23). VIN– ...
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... AGND IN1 ADC AD7892-2 3 IN2 POWER SUPPLY 5V GND 0.1µ AGND DD AD627 AD7892-2 ADC 5 3 Figure 48. Optimal Ground Practice in a Single-Supply Environment Rev Page DIGITAL POWER SUPPLY GND +5V V DGND 12 AGND DD MICRO- PROCESSOR V DGND 12 ...
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... Capacitor C1 and Capacitor C2 must be ±5% tolerance devices to avoid degrading the common- mode rejection of the circuit. Either the traditional 5% silver mica units or Panasonic ±2% PPS film capacitors are recommended. Rev Page AD627 ( 0.33µF 0.01µF R AD627 V G OUT REFERENCE 0.33µF 0.01µF –V S ...
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... A programmed gain on the AD627 of 100 (R 2.1 kΩ) and a voltage on the AD627 REF pin result in the output voltage of the AD627 ranging from 1.110 V to 3.077 V relative to ground. For a different input range or different ...
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... LINE 4–20mA TRANSDUCER IMPEDANCE 5V 0.1µF AIN 0 AD627 AD627 24.9Ω AIN 7 REF Figure 52 Receiver Circuit Rev Page AD627 5V 5V 0.1µF 0.1µ REF DD DD ADuC812 MICROCONVERTER ® AGND DGND ...
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... AD627ARZ-RL −40°C to +85°C AD627BN −40°C to +85°C 1 AD627BNZ −40°C to +85°C AD627BR −40°C to +85°C AD627BR-REEL −40°C to +85°C AD627BR-REEL7 −40°C to +85°C 1 AD627BRZ −40°C to +85°C 1 AD627BRZ-RL −40°C to +85°C 1 AD627BRZ-R7 − ...