ad8429 Analog Devices, Inc., ad8429 Datasheet
ad8429
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ad8429 Summary of contents
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... The AD8429 reliably amplifies fast changing signals. Its current feedback architecture provides high bandwidth at high gain, for example, 1.2 MHz 100. The design includes circuitry to im- prove settling time after large input voltage transients. The AD8429 was designed for excellent distortion performance, allowing use in demanding applications such as vibration analysis. ...
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... AD8429 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Pin Connection Diagram ................................................................ 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Absolute Maximum Ratings............................................................ 6 Thermal Resistance ...................................................................... 6 ESD Caution.................................................................................. 6 Pin Configuration and Function Descriptions............................. 7 Typical Performance Characteristics ............................................. 8 Theory of Operation ...................................................................... 15 REVISION HISTORY 4/11—Revision 0: Initial Version Architecture ................................................................................ 15 Gain Selection............................................................................. 15 Reference Terminal .................................................................... 15 Input Voltage Range................................................................... 16 Layout ...
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... AD8429 Unit nV/√Hz nV/√Hz μV p-p nV p-p pA/√Hz pA p-p μV μV/°C μV μV/° pA/°C nA pA/°C MHz ...
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... AD8429 Parameter Test Conditions/Comments Settling Time 0.01 step 100 G = 1000 Settling Time 0.001 step 100 G = 1000 Slew Rate 100 THD First five harmonics kHz kΩ 100 G = 1000 THD + kHz, R ...
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... Differential and common-mode input impedance can be calculated from the pin impedance Input voltage range of the AD8429 input stage only. The input range can depend on the common-mode voltage, differential voltage, gain, and reference voltage. See the Input Voltage Range section for more details. ...
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... AD8429 ABSOLUTE MAXIMUM RATINGS Table 2. Parameter Supply Voltage Output Short-Circuit Current Duration 1 Maximum Voltage at –IN, +IN 1 Differential Input Voltage Gain ≤ > Gain > 50 Gain ≥ 50 Maximum Voltage at REF Storage Temperature Range Specified Temperature Range Maximum Junction Temperature ESD Human Body Model ...
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... Reference Voltage Terminal. Drive this terminal with a low impedance voltage source to level shift the output Output Terminal. OUT 8 +V Positive Power Supply Terminal. S AD8429 – OUT R REF +IN – TOP VIEW (Not to Scale) Figure 3. Pin Configuration pins to set the gain kΩ/R G Rev Page AD8429 ). G ...
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... AD8429 TYPICAL PERFORMANCE CHARACTERISTICS T = 25° ±15 kΩ, unless otherwise noted. S REF ±15V ±12V ± –5 –10 –15 –15 –10 –5 0 OUTPUT VOLTAGE (V) Figure 4. Input Common-Mode Voltage vs. Output Voltage, Dual Supply ±5 V, ±12 V, ± ...
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... Rev Page – 105 120 TEMPERATURE (°C) GAIN = 1 –25 – TEMPERATURE (°C) –30 – TEMPERATURE (°C) Figure 15. Supply Current vs. Temperature ( AD8429 3 – 2.5 2.0 1.5 1.0 0.5 0 135 110 125 110 130 ...
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... AD8429 SHORT –10 –20 I SHORT– –30 –40 –50 –40 –25 – TEMPERATURE (°C) Figure 16. Short-Circuit Current vs. Temperature ( – –40 –25 – TEMPERATURE (°C) Figure 17. Slew Rate vs. Temperature – ...
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... Figure 26. RTI Voltage Noise Spectral Density vs. Frequency GAIN = Figure 27. 0 RTI Voltage Noise ( 1000) Rev Page AD8429 GAIN = 1000 –8 –6 –4 – OUTPUT VOLTAGE ( kΩ L ...
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... AD8429 100 1k FREQUENCY (Hz) Figure 28. Current Noise Spectral Density vs. Frequency 50pA/DIV Figure 29. 0 Current Noise ±15V ± 100 1k 10k 100k FREQUENCY (Hz) Figure 30. Large Signal Frequency Response 5V/DIV ...
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... Figure 38. Small Signal Response (G = 1000 1µs/DIV 50mV/DIV = 100 pF Figure 39. Small Signal Response with Various Capacitive Loads (G = 1), L Rev Page AD8429 1µs/DIV = 10 kΩ 100 10µs/DIV = 10 kΩ 100 ...
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... AD8429 1400 1200 1000 SETTLED TO 0.001% 800 SETTLED TO 0.01% 600 400 200 STEP SIZE (V) Figure 40. Settling Time vs. Step Size ( LOAD SECOND HARMONIC 2kΩ LOAD 600Ω LOAD 0.1 0.01 0.001 0.0001 0.00001 10 100 1k FREQUENCY (Hz) Figure 41. Second Harmonic Distortion vs. Frequency ( ...
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... The AD8429 defaults when no gain resistor is used. Add the tolerance and gain drift of the R specifications of the AD8429 to determine the total gain accu- racy of the system. When the gain resistor is not used, gain error and gain drift are minimal. ...
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... LAYOUT To ensure optimum performance of the AD8429 at the PCB level, care must be taken in the design of the board layout. The pins of the AD8429 are arranged in a logical manner to aid in this task –IN ...
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... INPUT PROTECTION Do not allow the inputs of the AD8429 to exceed the ratings stated in the Absolute Maximum Ratings section of this data sheet. If this cannot be done, protection circuitry can be added in front of the AD8429 to limit the current into the inputs to a maximum current MAX Input Voltages Beyond the Rails ...
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... Choose values of R and C that minimize RFI. A mismatch C between R × the positive input and R × input degrades the CMRR of the AD8429. By using a value of C that is one magnitude larger than mismatch is reduced, and performance is improved. Resistors add noise; therefore, the choice of resistor and capacitor values depends on the desired tradeoff between noise, input impedance at high frequencies, and RFI immunity ...
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... Figure 55. 8-Lead Standard Small Outline Package [SOIC_N] Narrow Body (R-8) Dimensions shown in millimeters and (inches) Package Description 8-Lead SOIC_N 8-Lead SOIC_N, 7” Tape and Reel 8-Lead SOIC_N 8-Lead SOIC_N, 7” Tape and Reel Rev Page 0.50 (0.0196) 45° 0.25 (0.0099) 1.27 (0.0500) 0.40 (0.0157) Package Option R-8 R-8 R-8 R-8 AD8429 ...
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... AD8429 NOTES ©2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D09730-0-4/11(0) Rev Page ...