AD8656 Analog Devices, AD8656 Datasheet
AD8656
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AD8656 Summary of contents
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... The AD8655/AD8656 are the industry’s lowest noise, precision CMOS amplifiers. They leverage the Analog Devices DigiTrim® technology to achieve high dc accuracy. The AD8655/AD8656 provide low noise (2.7 nV/√ kHz), low THD + N (0.0007%), and high precision performance (250 μV max over low voltage applications. The ability ...
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... Changes to Features Section............................................................ 1 Updated Outline Dimensions ....................................................... 19 Changes to Ordering Guide .......................................................... 19 Added Automotive Products Section .......................................... 19 6/05—Rev Rev. A Added AD8656 ...................................................................Universal Added Figure 2 and Figure 4........................................................... 1 Changes to Specifications ................................................................ 3 Changed Caption of Figure 12 and Added Figure 13 .................. 7 Replaced Figure 16 ........................................................................... 7 Changed Caption of Figure 37 and Added Figure 38 ................ 11 Replaced Figure 47 ...
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... THD + kΩ kHz GBP kΩ 0.1 step Rev Page AD8655/AD8656 Min Typ Max 50 250 550 0.4 2 500 10 500 100 = 0 V 100 110 ...
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... AD8655/AD8656 25°C, unless otherwise specified 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 OUTPUT CHARACTERISTICS Output Voltage High Output Voltage Low ...
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... Table 4. Package Type 8-Lead MSOP (RM) 8-Lead SOIC (R) 1 θ is specified for worst-case conditions; that is, θ JA soldered in the circuit board for surface-mount packages. Rev Page AD8655/AD8656 1 θ θ Unit JA JC 210 45 °C/W 158 43 ° ...
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... AD8655/AD8656 TYPICAL PERFORMANCE CHARACTERISTICS –150 –100 – (μV) OS Figure 5. Input Offset Voltage Distribution 150.0 100.0 50.0 0.0 –50.0 –100.0 –150.0 – TEMPERATURE (°C) Figure 6. Input Offset Voltage vs. Temperature 0.2 0.4 0.6 0.8 1.0 |TCV | (μV/°C) OS Figure 7. |TCV | Distribution ...
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... CURRENT LOAD (mA) Figure 12. AD8655 Output Voltage to Supply Rail vs. Current Load 10000 1000 100 0 CURRENT LOAD (mA) Figure 13. AD8656 Output Swing vs. Current Load 4.996 4.994 4.992 4.990 4.988 4.986 4.984 4.982 100 150 V OL 200 250 120 = ±2.5V ...
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... AD8655/AD8656 110.00 107.00 104.00 101.00 98.00 95.00 92.00 – TEMPERATURE (°C) Figure 17. Large Signal CMRR vs. Temperature 100 +PSRR 80 –PSRR 100 1k 10k 100k FREQUENCY (Hz) Figure 18. Small Signal PSSR vs. Frequency 110. ±2.5V S 108.00 106.00 104.00 102.00 100.00 – TEMPERATURE (°C) Figure 19. Large Signal PSSR vs. Temperature V = ± ...
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... Figure 25. Closed-Loop Gain vs. Frequency –45 = 11.5pF –90 –135 –180 –225 10M 100M 100 150 V = ±2. Ω 47pF L 10M 100M Rev Page AD8655/AD8656 10k 100k 1M FREQUENCY (Hz) Figure 26. Maximum Output Swing vs. Frequency ±2. 100pF L GAIN = + ...
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... AD8655/AD8656 ±2. 200mV – + 100 150 200 CAPACITANCE (pF) Figure 29. Small Signal Overshoot vs. Load Capacitance T 300mV ±2.5V OUT 300mV IN GAIN = –10 RECOVERY TIME = 240ns –2.5V 400ns/DIV Figure 30. Negative Overload Recovery Time ...
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... Rev Page AD8655/AD8656 10000 1000 100 0 CURRENT LOAD (mA) Figure 38. AD8656 Output Swing vs. Current Load 2.698 V = ±1.35V S LOAD CURRENT = 1mA 2.694 2.690 2.686 2.682 2.678 2.674 – TEMPERATURE (°C) Figure 39. Output Voltage Swing High vs. Temperature ...
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... AD8655/AD8656 OUT 2 20 μ s/DIV Figure 41. No Phase Reversal V = ±1.35V 50pF L GAIN = +1 2 TIME (10μs/DIV) Figure 42. Large Signal Response T 2 TIME (1μs/DIV) Figure 43. Small Signal Response ±1.35V 50pF Figure 44 ...
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... V = ±1.35V 50mV 1MΩ 47pF L 1M 10M 100M Rev Page AD8655/AD8656 V = ±1.35V 11.5pF LOAD PHASE MARGIN = 54° 10k 100k 1M 10M FREQUENCY (Hz) Figure 50. Open-Loop Gain and Phase vs. Frequency 90.00 80.00 – TEMPERATURE (°C) Figure 51 ...
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... AD8655/AD8656 3.0 2 1.35V 2. LOAD 1.5 1.0 0.5 0 10k 100k FREQUENCY (Hz) Figure 53. Maximum Output Swing vs. Frequency 1000 V = ±1.35V S 100 G = +100 0.1 100 1k 10k 100k FREQUENCY (Hz) Figure 54. Output Impedance vs. Frequency –100 –120 –140 1M 10M 10M 100M Rev Page 10k Ω ...
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... The open- loop gain of the AD8655/AD8656 with a load of 10 kΩ is typically 110 dB. The AD8655/AD8656 can be used in any precision op amp application ...
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... See the Driving Capacitive Loads section. DRIVING CAPACITIVE LOADS Although the AD8655/AD8656 can drive capacitive loads up to 500 pF without oscillating, a large amount of ringing is present when operating the part with input frequencies above 100 kHz. ...
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... Data Sheet THD Readings vs. Common-Mode Voltage Total harmonic distortion of the AD8655/AD8656 is well below 0.0007% with a load of 1 kΩ. This distortion is a function of the circuit configuration, the voltage applied, and the layout, in addition to other factors. +2.5V – AD8655 + –2. Figure 59. THD + N Test Circuit ...
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... Poor PC board layout, contaminants, and the board insulator material can create leakage currents that are much larger than the input bias current of the AD8655/AD8656. Any voltage differential between the inputs and nearby traces creates leakage currents through the PC board insulator, for example, 1 V/100 GΩ ...
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... W = Qualified for Automotive Applications. AUTOMOTIVE PRODUCTS The AD8656W model is available with controlled manufacturing to support the quality and reliability requirements of automotive applications. Note that these automotive models may have specifications that differ from the commercial models; therefore, designers should review the Specifications section of this data sheet carefully. Only the automotive grade product shown is available for use in automotive applications ...
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... AD8655/AD8656 NOTES ©2005–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D05304-0-9/11(B) Rev Page Data Sheet ...