AD8221 Analog Devices, AD8221 Datasheet
AD8221
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AD8221 Summary of contents
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... V input voltages are encountered. The AD8221 is available in a low cost 8-lead SOIC and 8-lead MSOP, both of which offer the industry’s best performance. The MSOP requires half the board space of the SOIC, making it ideal for multichannel or space-constrained applications ...
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... AD8221 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Connection Diagram ....................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 8 Thermal Characteristics .............................................................. 8 ESD Caution.................................................................................. 8 Typical Performance Characteristics ............................................. 9 Theory of Operation ...................................................................... 16 Gain Selection ............................................................................. 17 REVISION HISTORY 9/07—Rev Rev. B Changes to Features.......................................................................... 1 Changes to Table 1 Layout............................................................... 3 Changes to Table 2 Layout............................................................... 5 Changes to Figure 15...................................................................... 11 Changes to Figures 32 ...
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... ± 0.0001 AD8221 Unit nV/√Hz nV/√Hz μV p-p μV p-p μV p-p fA/√Hz pA p-p μV μV μV/°C μV mV μV/° pA/° pA/°C kΩ μA ...
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... AD8221 Parameter Conditions POWER SUPPLY Operating Range V S Quiescent Current Over Temperature T = −40°C to +85°C DYNAMIC RESPONSE Small Signal −3 dB Bandwidth 100 G = 1000 Settling Time 0.01 step 100 G = 1000 Settling Time 0.001 step 100 G = 1000 Slew Rate 100 GAIN (49.4 kΩ/R ...
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... AD8221 Unit °C °C Unit nV/√Hz nV/√Hz μV p-p μV p-p μV p-p fA/√Hz pA p-p μV μV μV/°C μV mV μV/° pA/° ...
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... AD8221 Parameter REFERENCE INPUT Voltage Range Gain to Output POWER SUPPLY Operating Range Quiescent Current Over Temperature DYNAMIC RESPONSE Small Signal –3 dB Bandwidth 100 G = 1000 Settling Time 0.01 100 G = 1000 Settling Time 0.001 100 G = 1000 Slew Rate GAIN Gain Range Gain Error ...
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... OS OSI OSO 2 Does not include the effects of external resistor R 3 One input grounded See Typical Performance Characteristics for expected operation between 85°C to 125°C. Conditions . G Rev Page AD8221 ARM Grade Min Typ Max −40 +85 −40 +125 Unit °C °C ...
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... AD8221 ABSOLUTE MAXIMUM RATINGS Table 3. Parameter Supply Voltage Internal Power Dissipation Output Short-Circuit Current Input Voltage (Common-Mode) Differential Input Voltage Storage Temperature Range 1 Operating Temperature Range 1 Temperature range for specified performance is –40°C to +85°C. See Typical Performance Characteristics for expected operation from 85°C to 125°C. ...
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... Figure 8. Input Common-Mode Range vs. Output Voltage 100 Rev Page 500 0 –0.9 –0.6 –0.3 0 0.3 INPUT OFFSET CURRENT (nA) Figure 6. Typical Distribution of Input Offset Current ±5V S –15 –10 – OUTPUT VOLTAGE ( ±5V S –5 –15 –10 – OUTPUT VOLTAGE (V) AD8221 0.6 0.9 = ±15V ±15V ...
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... FREQUENCY (Hz) Figure 13. Negative PSRR vs. Frequency, RTI ( 1000) BEST AVAILABLE FET INPUT IN-AMP GAIN = 1 1k BEST AVAILABLE FET INPUT IN-AMP GAIN = 1000 AD8221 GAIN = 1 AD8221 GAIN = 1000 10 10 100 1k 10k 100k SOURCE RESISTANCE (Ω) Figure 14. Total Drift vs. Source Resistance 100k 1M ...
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... S 100k 1M 0 Figure 20. Output Voltage Swing vs. Supply Voltage Rev Page – 100 120 TEMPERATURE (°C) Figure 18. CMR vs. Temperature SUPPLY VOLTAGE (± 10kΩ 2kΩ 2kΩ 10kΩ SUPPLY VOLTAGE (±V) AD8221 140 20 20 ...
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... AD8221 ±15V 100 LOAD RESISTANCE (Ω) Figure 21. Output Voltage Swing vs. Load Resistance +V –0 S –1 –2 – – OUTPUT CURRENT (mA) Figure 22. Output Voltage Swing vs. Output Current –10 –8 –6 –4 – OUTPUT VOLTAGE (V) Figure 23. Gain Nonlinearity 10k SOURCING SINKING ±15V S 100 Figure 26. Voltage Noise Spectral Density vs. Frequency ( 1000 kΩ ...
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... Figure 31. Large Signal Frequency Response 5V/DIV 0.002%/DIV 10k Figure 32. Large Signal Pulse Response and Settling Time (G = 1), 0.002%/DIV Rev Page AD8221 1s/DIV Figure 30. 0 Current Noise V = ±15V S GAIN = 1 GAIN = 10, 100, 1000 10k 100k 1M FREQUENCY (Hz) 7.9µs TO 0.01% 8.5µs TO 0.001% ...
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... AD8221 5V/DIV 4.9µs TO 0.01% 0.002%/DIV 5.6µs TO 0.001% Figure 33. Large Signal Pulse Response and Settling Time (G = 10), 0.002%/DIV 5V/DIV 10.3µs TO 0.01% 0.002%/DIV 13.4µs TO 0.001% Figure 34. Large Signal Pulse Response and Settling Time (G = 100), 0.002%/DIV 5V/DIV 83µ ...
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... Figure 39. Small Signal Response 1000 kΩ SETTLED TO 0.001% SETTLED TO 0.01 OUTPUT VOLTAGE STEP SIZE (V) Figure 40. Settling Time vs. Step Size ( 1000 100 100µs/DIV Figure 41. Settling Time vs. Gain for Step = 100 Rev Page AD8221 SETTLED TO 0.001% SETTLED TO 0.01% 10 100 1000 GAIN ...
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... R1, architectures at higher gains maintain precision even at low input levels, special attention was given to the design and layout of the AD8221, resulting in an in-amp whose performance satisfies the most demanding applications. A unique pinout enables the AD8221 to meet a CMRR specification kHz ( and 110 kHz (G = 1000) ...
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... The AD8221 defaults when no gain resistor is used. Gain accuracy is determined by the absolute tolerance of R The TC of the external gain resistor increases the gain drift of the instrumentation amplifier. Gain error and gain drift are kept to a minimum when the gain resistor is not used. ...
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... For example, a voltage source can be tied to the REF pin to level-shift the output so that the AD8221 can interface with an ADC. The allowable reference voltage range is a function of the gain, input, and supply voltage. The REF pin should not exceed either +V or – ...
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... By using a value the mismatch is reduced, and therefore, performance is improved. PRECISION STRAIN GAGE The low offset and high CMRR over frequency of the AD8221 make it an excellent candidate for bridge measurements. As shown in Figure 49, the bridge can be directly connected to the inputs of the amplifier. 350Ω ...
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... The fourth benefit of this interface circuit is that the acquisition time of the AD8221 is reduced by a factor of 2. With the help of the OP27, the AD8221 only needs to deliver one-half of the full swing; therefore, signals can settle more quickly. Lastly, the AD8022 settles quickly, which is helpful because the shorter the settling time, the more bits that can be resolved when the ADC acquires data ...
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... REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN. Figure 53. 8-Lead Standard Small Outline Package [SOIC_N] Narrow Body (R-8) Dimensions shown in millimeters and (inches) Rev Page 0.80 8° 0.60 0° 0.40 0.50 (0.0196) 45° 0.25 (0.0099) 1.27 (0.0500) 0.40 (0.0157) AD8221 ...
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... AD8221ARZ-R7 –40°C to +85°C 2 AD8221ARZ-RL –40°C to +85°C AD8221ARM –40°C to +85°C AD8221ARM-REEL –40°C to +85°C AD8221ARM REEL7 –40°C to +85°C 2 AD8221ARMZ –40°C to +85°C 2 AD8221ARMZ-R7 –40°C to +85°C 2 AD8221ARMZ-RL –40°C to +85°C AD8221BR – ...
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... NOTES Rev Page AD8221 ...
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... AD8221 NOTES ©2003–2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D03149–0–9/07(B) Rev Page ...