AD8657 Analog Devices, AD8657 Datasheet
AD8657
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AD8657 Summary of contents
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... The AD8657 is a dual, micropower, precision, rail-to-rail input/output amplifier optimized for low power and wide operating supply voltage range applications. The AD8657 operates from 2 with a typical quiescent supply current of 18 μA. It uses the Analog Devices, Inc., patented DigiTrim® trimming technique, which achieves low offset voltage ...
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... AD8657 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 Pin Configuration ............................................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Electrical Characteristics—2.7 V Operation ............................ 3 Electrical Characteristics—10 V Operation ............................. 4 Electrical Characteristics—18 V Operation ............................. 5 Absolute Maximum Ratings ............................................................ 6 Thermal Resistance ...................................................................... 6 ESD Caution .................................................................................. 6 Typical Performance Characteristics ............................................. 7 REVISION HISTORY 3/11—Rev Rev. A Added LFCSP Package Information ........................... Throughout Added Figure 2, Renumbered Subsequent Figures ................... 1 Changes to Table 2, Introductory Text ...
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... A ≤ +125° ±4 20 105 125 170 60 105 0.1 AD8657 Unit µ μV/°C GΩ Ω µA µA V/ms µs kHz ...
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... AD8657 ELECTRICAL CHARACTERISTICS—10 V OPERATION 25°C, unless otherwise specified Table 3. Parameter INPUT CHARACTERISTICS Offset Voltage Input Bias Current Input Offset Current Input Voltage Range Common-Mode Rejection Ratio Large Signal Voltage Gain Offset Voltage Drift Input Resistance ...
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... A ≤ +125° ±12 15 105 125 200 60 105 0.1 AD8657 Unit µ μV/°C GΩ Ω µA µA V/ms µs ...
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... AD8657 ABSOLUTE MAXIMUM RATINGS Table 4. Parameter Rating Supply Voltage 20.5 V Input Voltage (V−) − 300 mV to (V+) + 300 mV Input Current 1 ±10 mA Differential Input Voltage ±V SY Output Short-Circuit Indefinite Duration to GND Temperature Range Storage −65°C to +150°C Operating −40°C to +125°C Junction − ...
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... TCV (µV/°C) OS Figure 7. Input Offset Voltage Drift Distribution 300 V = 18V SY 200 100 0 –100 –200 –300 (V) CM Figure 8. Input Offset Voltage vs. Common-Mode Voltage AD8657 V = 18V ≤ +125° ...
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... AD8657 2.0 1.5 1.0 0.5 0 –0.5 –1.0 –1.5 –2.0 0 0.3 0.6 0.9 1.2 1.5 V (V) CM Figure 9. Input Offset Voltage vs. Common-Mode Voltage 2.0 V 1.5 –40°C ≤ T 1.0 0.5 0 –0.5 –1.0 –1.5 –2.0 0 0.3 0.6 0.9 1.2 1.5 V (V) CM Figure 10. Input Offset Voltage vs. Common-Mode Voltage 10000 V = 2.7V SY 1000 100 – 0 TEMPERATURE (°C) Figure 11. Input Bias Current vs. Temperature ...
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... V ( 18V SY –40°C +25°C +85°C +125°C 0.01 0 LOAD CURRENT (mA Supply Rail vs. Load Current 18V SY –40°C +25°C +85°C +125°C 0.01 0 LOAD CURRENT (mA Supply Rail vs. Load Current OL AD8657 16 18 100 100 ...
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... AD8657 2.700 R = 1MΩ L 2.699 2.698 2.697 R = 100kΩ L 2.696 V = 2.7V SY 2.695 –50 – TEMPERATURE (°C) Figure 21. Output Voltage (V ) vs. Temperature 2. –50 – TEMPERATURE (°C) Figure 22. Output Voltage (V ) vs. Temperature 2. ...
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... Figure 30. Supply Current vs. Temperature V = 18V SY PHASE R = 1MΩ L GAIN C = 10pF 100pF L 10k 100k FREQUENCY (Hz) Figure 31. Open-Loop Gain and Phase vs. Frequency V = 18V 100 10k 100k FREQUENCY (Hz) Figure 32. Closed-Loop Gain vs. Frequency AD8657 125 135 –45 –90 –135 1M 1M ...
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... AD8657 1000 A = 100 100 100 1k FREQUENCY (Hz) Figure 33. Output Impedance vs. Frequency 140 V = 2.7V SY 120 V = 2.4V CM 100 100 1k 10k FREQUENCY (Hz) Figure 34. CMRR vs. Frequency 100 100 1k 10k FREQUENCY (Hz) Figure 35. PSRR vs. Frequency V = 2.7V SY 10k 100k 100k 2.7V ...
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... Figure 41. Small Signal Transient Response 1000 10 Figure 42. Small Signal Overshoot vs. Load Capacitance = ±1.35V 1MΩ 100pF L = ±1.35V Rev Page AD8657 V = 18V SY OS 10mV p-p IN OS– 1MΩ L 100 CAPACITANCE (pF ± 1MΩ ...
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... AD8657 0 INPUT –0.2 –0.4 OUTPUT TIME (40µs/DIV) Figure 45. Positive Overload Recovery 0.4 0.2 INPUT 0 OUTPUT TIME (40µs/DIV) Figure 46. Negative Overload Recovery INPUT ERROR BAND OUTPUT TIME (10µs/DIV) Figure 47. Positive Settling Time to 0. ±1. –10 – 1MΩ ...
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... Rev Page =18V 100kΩ 10pF L INPUT OUTPUT ERROR BAND TIME (10µs/DIV) Figure 54. Negative Settling Time to 0. 18V SY 100 1k 10k 100k FREQUENCY (Hz) Figure 55. Voltage Noise Density vs. Frequency V = 18V SY TIME (2s/DIV) Figure 56. 0 Noise AD8657 +5mV 0 –5mV 1M ...
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... AD8657 3.0 2.5 2.0 1.5 1.0 0 100 1k 10k FREQUENCY (Hz) Figure 57. Output Swing vs. Frequency 100 0.2V rms 1MΩ 0.1 0.01 10 100 1k FREQUENCY (Hz) Figure 58. THD + N vs. Frequency 2.7V SY – 1MΩ –100 V –40 – 0.5V p-p IN – 1.5V p 2.6V p-p IN –100 –120 –140 100 1k FREQUENCY (Hz) Figure 59 ...
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... Figure 23 and Figure 26 for more details). The AD8657 achieves its high performance by using low voltage MOS devices for its differential inputs. These low voltage MOS devices offer excellent noise and bandwidth per unit of current. ...
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... Figure 64 shows the input and output waveforms of the AD8657 configured as a unity-gain buffer with a supply voltage of ±9 V and a resistive load of 1 MΩ. With an input voltage of ±9 V, the AD8657 allows the output to swing very close to both rails. Additionally, it does not exhibit phase reversal. ...
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... Figure 69 and Figure 70 show the AD8657 configured as a com- parator, with 100 kΩ resistors in series with the input pins. Any unused channels are configured as buffers with the input voltage kept at the midpoint of the power supplies ...
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... For instance, wires and PCB traces can act as antennas and pick up high frequency EMI signals. Precision op amps, such as the AD8657, do not amplify EMI or RF signals because of their relatively low bandwidth. However, due to the nonlinearities of the input devices, op amps can rectify these out-of-band signals ...
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... AREA 0.80 0.75 0.70 SEATING PLANE ORDERING GUIDE Model 1 Temperature Range AD8657ARMZ −40°C to +125°C AD8657ARMZ-R7 −40°C to +125°C AD8657ARMZ-RL −40°C to +125°C AD8657ACPZ-R7 −40°C to +125°C AD8657ACPZ-RL −40°C to +125° RoHS Compliant Part. 3.20 3.00 2.80 5. 3.20 4.90 3.00 4.65 1 2.80 4 PIN 1 0.65 BSC 0.95 15° ...
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... AD8657 NOTES Rev Page ...
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... NOTES Rev Page AD8657 ...
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... AD8657 NOTES ©2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D08804-0-3/11(A) Rev Page ...