AD8698 Analog Devices, AD8698 Datasheet
AD8698
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AD8698 Summary of contents
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... Multipole filters Integrator GENERAL DESCRIPTION The AD8698 is a high precision, rail-to-rail output, low noise, low input bias current operational amplifier. Offset voltage is a respectable 100 µV max and drift over temperature is below 2 µV/°C, eliminating the need for manual offset trimming. The AD8698 is ideal for high impedance sensors, minimizing offset errors due to input bias and offset currents ...
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... Thermal Resistance ...................................................................... 5 ESD Caution.................................................................................. 5 Typical Performance Characteristics............................................. 6 Applications .................................................................................... 14 Input Overvoltage Protection................................................... 14 Driving Capacitive Loads .......................................................... 14 REVISION HISTORY 4/04—Revision 0: Initial Version Instrumentation Amplifier ....................................................... 15 Composite Amplifier ................................................................. 15 Low Noise Applications ............................................................ 16 Driving ADCs ............................................................................. 16 Using the AD8698 in Active Filter Designs ........................... 16 Outline Dimensions....................................................................... 17 Ordering Guide .......................................................................... 17 Rev Page ...
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... V < +85° kΩ L GBP Ø p-p 0.1 Hz < f < kHz kHz n Rev Page AD8698 Min Typ Max Unit 20 100 µV 300 µV 0.6 2 µV/°C 700 pA 1500 pA 700 pA 1500 pA −13.5V 13.5 V 118 132 ...
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... AD8698 ±2 (@ unless otherwise noted Table 2. Parameter INPUT CHARACTERISTICS Offset Voltage Offset Voltage Drift Input Bias Current Input Offset Current Input Voltage Range Common-Mode Rejection Ratio Large Signal Voltage Gain Input Capacitance OUTPUT CHARACTERISTICS Output Voltage Swing (Ref ...
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... THERMAL RESISTANCE θ is specified for the worst-case conditions, i.e., θ JA for devices soldered in circuit boards for surface-mount packages Table 4. Thermal Resistance Package Type MSOP-8 (RM) SOIC-8 (R) Rev Page AD8698 is specified JA θ θ Unit JA JC 210 45 °C/W 158 43 °C/W ...
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... AD8698 TYPICAL PERFORMANCE CHARACTERISTICS 0.2 0.4 0.6 0.8 TCV (µV/°C) OS Figure 2. Input Offset Voltage Drift Distribution –100 –80 –60 –40 – (µV) OS Figure 3. Offset Voltage Distribution –400 –320 –240 –160 –80 ...
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... Rev Page OUT = ±15V S = 200mV p –100 V TIME (10µs/DIV) Figure 11. Positive Overvoltage Recovery V = ±15V 200mV –100 OUT TIME (400µs/DIV) Figure 12. Negative Overvoltage Recovery V = ±15V S 10k 100k 1M FREQUENCY (Hz) Figure 13. CMRR vs. Frequency AD8698 10M ...
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... AD8698 100 80 60 –PSRR 100 1k 10k FREQUENCY (Hz) Figure 14. PSRR vs. Frequency V = ±15V S TIME (1s/DIV) Figure 15. Input Voltage Noise 100 FREQUENCY (Hz) Figure 16. Voltage Noise Density vs. Frequency 100 V = ±15V S 10 +PSRR 1 0.1 100k 1M 0 –10 –20 –30 –40 –60 14. ±15V S 14 ...
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... Figure 25. ∆ Output Voltage Swing from Rails vs. Load Current Rev Page ±15V S –40 – TEMPERATURE (°C) Figure 23. PSRR vs. Temperature V = ±15V S –40 – TEMPERATURE (°C) Figure 24. ∆ Input Bias Current vs. Temperature V = ±15V LOAD CURRENT (mA) AD8698 100 100 20 ...
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... AD8698 3 ±15V S 3.0 2.5 2.0 1.5 –60 –40 – TEMPERATURE (°C) Figure 26. Supply Current vs. Temperature 0 –20 –40 –60 –80 –100 –120 –140 1k 10k 100k FREQUENCY (Hz) Figure 27. Channel Separation –100 –80 –60 –40 – (µV) OS Figure 28. Offset Voltage Distribution ...
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... Rev Page ±2. 200mV p –100 OUT TIME (4µs/DIV) Figure 35. Negative Overvoltage Recovery V = ±2.5V S 10k 100k 1M FREQUENCY (Hz) Figure 36. CMRR vs. Frequency V = ±2.5V S +PSRR –PSRR 100 1k 10k 100k FREQUENCY (Hz) Figure 37. PSRR vs. Frequency AD8698 10M 1M ...
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... AD8698 20 – – –20 –30 –60 –40 – TEMPERATURE (°C) Figure 38. Short-Circuit Current vs. Temperature 2.46 2.45 2.44 2.43 2.42 2.41 2.40 2.39 2.38 –60 –40 – TEMPERATURE (°C) Figure 39. Output Swing vs. Temperature 2.5 2.3 2.1 1.9 1.7 1.5 –60 –40 – TEMPERATURE (°C) Figure 40. Output Voltage Swing vs. Temperature V = ±2.5V S –10 –20 – ...
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... TIME (400µs/DIV) Figure 46. No Phase Reversal 3 ±2.5V S 2.5 2.0 1.5 1.0 0 –20 –40 –60 –80 –100 –120 –140 60 80 100 1k Rev Page AD8698 SUPPLY VOLTAGE (V) Figure 47. Supply Current vs. Supply Voltage V = ±2.5V S 10k 100k 1M FREQUENCY (Hz) Figure 48. Channel Separation 35 10M ...
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... This is particularly important in positive unity gain configurations, the worst case for stability. Figure 49 shows the output of the AD8698 with load in response to a 400 mV signal at its positive input; the overshoot is less than 25% without any external compensation. Using a simple “ ...
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... AD8698 100 Figure 53. Three Op Amp In-Amp COMPOSITE AMPLIFIER The dc accuracy of the AD8698 and the ac performance of the OP184 are combined in the circuit shown in Figure 54. The composite amplifier provides a higher bandwidth, a lower offset voltage, and a higher loop, thereby reducing the gain error substantially. ...
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... AD8698 LOW NOISE APPLICATIONS In some applications critical to minimize the noise, and although the AD8698 has a low noise of typically 8 nV/ √ kHz, paralleling the two amplifiers within the same package reduces the total noise referred to the input to approximately 5.5 nV/ √ Hz. This simple technique is depicted in Figure 55. ...
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... Figure 59. 8-Lead Small Outline IC [SOIC] (RM-8)—Dimensions shown in millimeters ORDERING GUIDE Model Temperature Package AD8698ARM-R2 –40°C to +85°C AD8698ARM-REEL –40°C to +85°C AD8698AR –40°C to +85°C AD8698AR-REEL –40°C to +85°C AD8698AR-REEL7 –40°C to +85°C 5.00 (0.1968) 4.80 (0.1890 6.20 (0.2440) 4.00 (0.1574) 5.80 (0.2284) 3.80 (0.1497 ...
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... AD8698 NOTES Rev Page ...
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... NOTES Rev Page AD8698 ...
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... AD8698 NOTES © 2004 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D04807-0-4/04(0) Rev Page ...