AD8224 Analog Devices, AD8224 Datasheet
AD8224
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AD8224 Summary of contents
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... Its ability to run on a single 5 V supply eliminates the need for higher voltage, dual supplies. The AD8224 draws a maximum of 750 μA of quiescent current per amplifier, making it ideal for battery-powered devices. In addition, the AD8224 can be configured as a single-channel, differential output instrumentation amplifier ...
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... AD8224 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 9 Thermal Resistance ...................................................................... 9 ESD Caution.................................................................................. 9 Pin Configuration and Function Descriptions........................... 10 Typical Performance Characteristics ........................................... 11 Theory of Operation ...................................................................... 19 Gain Selection ............................................................................. 19 Reference Terminal .................................................................... 20 REVISION HISTORY 1/07—Revision 0: Initial Version Layout .......................................................................................... 20 Solder Wash................................................................................. 21 Input Bias Current Return Path ...
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... OS OSI OSO T = −40°C to +85° −40°C to +85°C ± ± −40°C to +85° −40°C to +85° − Rev Page AD8224 ± Grade Min Typ Max Unit ...
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... Differential and common-mode input impedance can be calculated from the pin impedance The AD8224 can operate diode drop below the negative supply, however the bias current increases sharply. The input voltage range reflects the maximum allowable voltage where the input bias current is within the specification. ...
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... V = ± Grade Min Typ Max 1500 800 120 14 5 4.3 8 4.6 9 AD8224 Unit kHz kHz kHz kHz μs μs μs μs μs μs μs μs V/μs Unit kHz kHz kHz kHz μs μs μs μs μs μs μs μ ...
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... AD8224 − 2 25° REF A individual instrumentation amplifier configured for a single-ended output or dual instrumentation amplifiers configured for differential outputs as shown in Figure 59. Table 5. Individual Amplifier—Single-Ended Configuration or Dual Amplifiers—Differential Output Configuration Parameter COMMON-MODE REJECTION RATIO (CMRR) CMRR with 1 kΩ ...
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... Differential and common-mode impedance can be calculated from the pin impedance The AD8224 can operate diode drop below the negative supply, but the bias current increases sharply. The input voltage range reflects the maximum allowable voltage where the input bias current is within the specification. ...
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... AD8224 − 2 25° REF A dynamic performance of each individual instrumentation amplifier. Table 6. Dynamic Performance of Each Individual Amplifier—Single-Ended Output Configuration, V Parameter DYNAMIC RESPONSE Small Signal Bandwidth − 100 G =1000 Settling Time 0.01 ...
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... If the thermal pad is soldered to the board, then it is also assumed it is connected to a plane. θ is 4.4°C/W. Maximum Power Dissipation The maximum safe power dissipation for the AD8224 is limited Rating by the associated rise in junction temperature (T ±18 V approximately 130°C, which is the glass transition temperature, See Figure 2 the plastic changes its properties ...
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... OUT2 15 OUT1 –IN1 1 PIN 1 12 –IN2 INDICATOR RG1 2 11 RG2 AD8224 RG1 3 10 RG2 TOP VIEW +IN1 4 +IN2 9 Figure 3. Pin Configuration Description Negative Input Instrumentation Amplifier (In-Amp) 1. Gain Resistor In-Amp 1. Gain Resistor In-Amp 1. Positive Input In-Amp 1. Positive Supply. Reference Adjust In-Amp 1. ...
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... XX 1 150 130 110 1s/DIV Rev Page AD8224 1 10 100 TIME (s) GAIN = 1000 BANDWIDTH LIMITED GAIN = 10 GAIN = 1 10 100 1k 10k 100k FREQUENCY (Hz) Figure 8. Positive PSRR vs. Frequency, RTI GAIN = 1000 GAIN = 1 GAIN = 10 GAIN = 100 ...
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... AD8224 INPUT OFFSET 9 CURRENT ±15 INPUT OFFSET CURRENT ± –15.1V INPUT BIAS CURRENT ±15 3 –5.1V INPUT BIAS CURRENT ±5 1 –1 –16 –12 –8 – COMMON-MODE VOLTAGE (V) Figure 10. Input Current vs. Common-Mode Voltage 10n 1n I BIAS 100p 10p 1p 0.1p –50 – TEMPERATURE (° ...
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... OUTPUT VOLTAGE (V) Figure 20. Gain Nonlinearity 1000 +13V ±15V SUPPLIES –14.8V, +5.5V +3V +14.9V, +5.5V –4.8V, +0.6V +4.95V, +0.6V ±5V SUPPLIES –4.8V, –3.3V +4.95V, –3.3V –14.8V, –8.3V +14.9V, –8.3V –5.3V –15.3V –12 –8 – OUTPUT VOLTAGE ( REF AD8224 ...
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... Figure 27. Output Voltage Swing vs. Supply Voltage, R Rev Page –1 +125°C –40°C –2 +25°C +85°C NOTES 1. THE AD8224 CAN OPERATE THE NEGATIVE SUPPLY, BUT THE BIAS CURRENT WILL INCREASE SHARPLY. +1 –40°C +25°C +85°C +125°C V – S –1 ...
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... I (mA) OUT S 47pF NO LOAD 100pF 20mV/DIV 5µs/DIV XX XXX ( ± REF 47pF 100pF NO LOAD 20mV/DIV 5µs/DIV XX XXX ( 2 REF AD8224 +25°C –40° 2.5 V REF XX XX ...
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... AD8224 35 GAIN = 10, 100, 1000 30 GAIN = 100 1k 10k 100k FREQUENCY (Hz) Figure 34. Output Voltage Swing vs. Large Signal Frequency Response XX 5V/DIV 5µs TO 0.01% 6µs TO 0.001% 0.002%/DIV XX XX XXX (X) Figure 35. Large Signal Pulse Response and Settle Time kΩ ± ...
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... Figure 45. Small Signal Pulse Response 100 Rev Page 20mV/DIV XXX = 2 kΩ 100 pF 2 REF 20mV/DIV XXX = 2 kΩ 100 pF 2 REF 20mV/DIV XXX = 2 kΩ 100 pF 2 REF AD8224 4µs/DIV 4µs/DIV 4µs/DIV ...
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... AD8224 20mV/DIV XXX Figure 46. Small Signal Pulse Response 1000 2 REF 15 10 SETTLED TO 0.001% 5 SETTLED TO 0.01 OUTPUT VOLTAGE STEP SIZE (V) Figure 47. Settling Time vs. Step Size ( ± 100 SETTLED TO 0.001 GAIN (V/V) Figure 48. Settling Time vs. Gain for Step, V 40µ ...
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... GAIN SELECTION Placing a resistor across the R AD8224. This is calculated by referring to Table using the following gain equation: Rev Page 20kΩ ...
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... Thermal Pad The AD8224 4 mm × LFCSP comes with a thermal pad. This pad is connected internally to +V left unconnected or connected to the positive supply rail. To preserve maximum pin compatibility with other dual instrumentation amplifiers, such as the AD8222, leave the pad unconnected ...
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... A stable dc voltage should be used to power the instrumentation amplifier. Noise on the supply pins can adversely affect performance. The AD8224 has two positive supply pins (Pin 5 and Pin 16) and two negative supply pins (Pin 8 and Pin 13). While the part functions with only one pin from each supply pair connected, both pins should be connected for specified performance and optimum reliability ...
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... OUT REF COMMON-MODE INPUT VOLTAGE RANGE + The 3-op amp architecture of the AD8224 applies gain and then removes the common-mode voltage. Therefore, internal nodes in the AD8224 experience a combination of both the gained signal and the common-mode signal. This combined signal can be limited by the voltage supplies even when the individual input and output signals are not ...
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... ADC can degrade total harmonic distortion (THD). For applications where THD performance is critical, the series resistor needs to be small. At worst, a small series resistor can load the AD8224, potentially causing the output to overshoot or ring. In such cases, a buffer amplifier, such as the be used after the AD8224 to drive the ADC. ...
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... The capacitive load from the cable may cause peaking in the AD8224 output response. To reduce peaking, use a resistor between the AD8224 and the cable. Because cable capacitance and desired output response vary widely, this resistor is best determined empirically. A good starting point is 50 Ω ...
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... COMPLIANT TO JEDEC STANDARDS MO-220-VGGC. Figure 63. 16-Lead Lead Frame Chip Scale Package [LFCSP_VQ × Body, Very Thin Quad (CP-16-13) Dimensions are shown in millimeters Product Description 16-Lead LFCSP_VQ 16-Lead LFCSP_VQ 16-Lead LFCSP_VQ Evaluation Board Rev Page 0.50 0.40 0. 2.65 2.50 SQ PAD 2. 0.25 MIN Package Option CP-16-13 CP-16-13 CP-16-13 AD8224 ...
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... AD8224 NOTES Rev Page ...
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... NOTES Rev Page AD8224 ...
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... AD8224 NOTES ©2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D06286-0-1/07(0) Rev Page ...