ADA4938-1ACPZ-R2 Analog Devices Inc, ADA4938-1ACPZ-R2 Datasheet
ADA4938-1ACPZ-R2
Specifications of ADA4938-1ACPZ-R2
Related parts for ADA4938-1ACPZ-R2
ADA4938-1ACPZ-R2 Summary of contents
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... ideal choice for driving high per- formance ADCs with resolutions bits from MHz bits from MHz. The output common-mode voltage is adjustable over a wide range, allowing the ADA4938 to match the input of the ADC. The internal common-mode feedback loop also provides exceptional output balance as well as suppression of even-order harmonic distortion products ...
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... ADA4938-1/ADA4938-2 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagrams ............................................................. 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Dual-Supply Operation ............................................................... 3 Single-Supply Operation ............................................................. 5 Absolute Maximum Ratings ............................................................ 7 Thermal Resistance ...................................................................... 7 ESD Caution .................................................................................. 7 Pin Configurations and Function Descriptions ........................... 8 Typical Performance Characteristics ............................................. 9 Test Circuts ...................................................................................... 17 Terminology .................................................................................... 18 REVISION HISTORY 10/09—Rev Rev. A Added Settling Time Parameter, Table 1 ....................................... 3 Changes to Linear Output Current Parameter, Table 1 ...
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... Overdrive Recovery Time NOISE/HARMONIC PERFORMANCE Second Harmonic Third Harmonic IMD IP3 Input Voltage Noise Noise Figure Input Current Noise Crosstalk (ADA4938-2) INPUT CHARACTERISTICS Offset Voltage Input Bias Current Input Resistance Input Capacitance Input Common-Mode Voltage CMRR OUTPUT CHARACTERISTICS Output Voltage Swing ...
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... ADA4938-1/ADA4938 ±OUT Performance OCM Table 2. Parameter V DYNAMIC PERFORMANCE OCM −3 dB Bandwidth Slew Rate Input Voltage Noise (RTI) V INPUT CHARACTERISTICS OCM Input Voltage Range Input Resistance Input Offset Voltage Input Bias Current V CMRR OCM Gain POWER SUPPLY Operating Range Quiescent Current Power Supply Rejection Ratio ...
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... Slew Rate Settling Time Overdrive Recovery Time NOISE/HARMONIC PERFORMANCE Second Harmonic Third Harmonic Input Voltage Noise Noise Figure Input Current Noise Crosstalk (ADA4938-2) INPUT CHARACTERISTICS Offset Voltage Input Bias Current Input Resistance Input Capacitance Input Common-Mode Voltage CMRR OUTPUT CHARACTERISTICS Output Voltage Swing ...
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... ADA4938-1/ADA4938 ±OUT Performance OCM Table 4. Parameter V DYNAMIC PERFORMANCE OCM −3 dB Bandwidth Slew Rate Input Voltage Noise (RTI) V INPUT CHARACTERISTICS OCM Input Voltage Range Input Resistance Input Offset Voltage Input Bias Current V CMRR OCM Gain POWER SUPPLY Operating Range Quiescent Current Power Supply Rejection Ratio ...
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... Even temporarily exceeding this temperature limit can change the stresses that the package exerts on the die, permanently shifting the parametric performance of the ADA4938. Exceeding a junction temperature of 150°C for an extended period can result in changes in the silicon devices, potentially causing failure. ...
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... Negative Output for Load Connection. Power-Down Pin −V Negative Supply Voltage Exposed Paddle. The exposed pad is not electrically connected to the device typically soldered to ground or a power plane on the PCB that is thermally conductive –OUT 10 +OUT 9 V OCM Table 8. ADA4938-2 Pin Function Descriptions Pin No 15 ...
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... 61.9 Ω 200 Ω + 1000 = 0.1 V p-p OUT 1000 = 0.1 V p-p OUT 1000 Figure 12. Large Signal Frequency Response for Various Temperatures = 0.1 V p-p Rev Page ADA4938-1/ADA4938 kΩ, unless otherwise noted –3 –6 – +3. – 100 FREQUENCY (MHz) Figure 10. Large Signal Frequency Response for Various Gains ...
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... ADA4938-1/ADA4938 –3 –6 –9 –12 – 1kΩ L – 100Ω 200Ω L – 100 FREQUENCY (MHz) Figure 13. Small Signal Frequency Response for Various Loads 0.1 V p-p OUT 3 0 –3 –6 – +3. – 100 FREQUENCY (MHz) Figure 14. Small Signal Frequency Response for ...
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... R = 1kΩ –0 100Ω –0 –0 200Ω –1 100 FREQUENCY (MHz) Figure 21. 0.1 dB Flatness Response for Various Loads, ADA4938- 0.1 V p-p OUT –3 –6 –9 –12 1000 1 = 402 Ω, Figure 22. Large Signal Frequency Response for Various Gains –3 – ...
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... ADA4938-1/ADA4938-2 –40 HD2 +5V S HD3 +5V S –50 HD2 ±5V S HD3 ±5V S –60 –70 –80 –90 –100 –110 –120 1 10 FREQUENCY (MHz) Figure 25. Harmonic Distortion vs. Frequency and Supply Voltage –40 HD2 HD3 –50 HD2 HD3 –60 HD2 HD3 –70 –80 –90 –100 – ...
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... Rev Page ADA4938-1/ADA4938-2 –PSRR +PSRR 1 10 100 FREQUENCY (MHz) Figure 34. PSRR vs. Frequency S22 S11 10 100 FREQUENCY (MHz) Figure 35. Return Loss (S11, S22) vs. Frequency R = 1kΩ 200Ω ...
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... ADA4938-1/ADA4938 100 FREQUENCY (MHz) Figure 37. Noise Figure vs. Frequency –2 –4 –6 V × 3.16 – OUT – TIME (5ns/DIV) Figure 38. Overdrive Recovery Time (Pulse Input –2 –4 –6 –8 V × 3.16 IN – OUT – 100 150 200 250 300 TIME (50ns/DIV) Figure 39. Overdrive Amplitude Characteristics (Triangle Wave Input) 500 – ...
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... V p-p OUT = 0.1 V p-p OUT –12 3.4 3.6 3.8 4 Figure 48 Rev Page ADA4938-1/ADA4938-2 3.0 2.5 2.0 1.5 1.0 0.5 0 TIME (1ns/DIV) Figure 46. Large Signal Transient Response 2.5 2.0 1.5 1.0 0.5 0 –0.5 –1.0 –1.5 – ...
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... OCM 1M 10M 100M Rev Page INPUT1, OUTPUT2 INPUT2, OUTPUT1 0 100 FREQUENCY (MHz) Figure 52. Crosstalk vs. Frequency for ADA4938 SETTLING ERROR TIME (1ns/DIV) Figure 53. 0.1% Settling Time 1000 1.0 0.5 0.1 0 –0.1 –0.5 –1.0 ...
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... Figure 55. Test Circuit for Output Balance 200Ω +5V 50Ω 200Ω FILTER V ADA4938 61.9Ω OCM 200Ω 27.5Ω –5V 200Ω Figure 56. Test Circuit for Distortion Measurements Rev Page ADA4938-1/ADA4938-2 1kΩ 50Ω 50Ω 0.1µF 412Ω FILTER 0.1µF 412Ω ...
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... ADA4938-1/ADA4938-2 TERMINOLOGY –FB ADA4938 +IN –OUT V OCM –IN +OUT +FB Figure 57. Circuit Definitions Differential Voltage The differential voltage is the difference between two node voltages. For example, the output differential voltage (or equivalently, output differential-mode voltage) is defined − OUT, dm +OUT −OUT where V and V refer to the voltages at the +OUT and +OUT − ...
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... ADA4938-x behaves much like a standard voltage feedback op amp and makes it easier to perform single-ended-to-differential conversions, common-mode level shifting, and amplifications of differential signals. Also like an op amp, the ADA4938-x has high input impedance and low output impedance. Two feedback loops are employed to control the differential and common-mode output voltages ...
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... Figure 59, the input impedance (R (+D and − the root-sum- nOD Figure 59. ADA4938 Configured for Balanced (Differential) Inputs For an unbalanced, single-ended input signal (see Figure 60), the input impedance is , ratio matching OCM Figure 60. ADA4938-x Configured for Unbalanced (Single-Ended) Input The input impedance of the circuit is effectively higher than it ...
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... R 200Ω 61.9Ω ADA4938 OCM 200Ω 27.4Ω – Figure 65. Complete Single-Ended-to-Differential System pin of the ADA4938-x is internally biased at a voltage OCM input to a common-mode OCM pin is approximately 10 kΩ. If multiple OCM 0.97V calculated F ⎞ = ⎟ 207 Ω ⎠ V), R ...
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... ADA4938-1/ADA4938-2 Table 10 and Table 11 list several common gain settings, associated resistor values, input impedances, and output noise densities for both balanced and unbalanced input configurations. Also shown Table 10. Differential Ground-Referenced Input, DC-Coupled; See Figure 59 Nominal Gain (V/V) R (Ω) R (Ω IN 200 200 ...
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... GROUND PLANE POWER PLANE BOTTOM METAL Figure 68. Cross-Section of a 4-Layer PCB (ADA4938-1) Showing a Thermal Via Connection to the Buried Ground Plane (Dimensions in mm) Bypass the power supply pins as close to the device as possible and directly to a nearby ground plane. Use high frequency ceramic chip capacitors recommended that two parallel bypass capa- citors (1000 pF and 0.1 μ ...
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... ADC, performs a single-ended-to- differential conversion, buffers the driving signal, and provides appropriate level shifting for dc coupling. The ADA4938-x is configured with dual ±5 V supplies and a gain of ~2 V/V for a single-ended input to differential output. The 76.8 Ω termination resistor, in parallel with the single- ended input impedance of 137 Ω ...
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... SEATING PLANE PIN 1 INDICATOR 1.00 12° MAX 0.85 0.80 SEATING PLANE ORDERING GUIDE Model Temperature Range 1 ADA4938-1ACPZ-R2 −40°C to +85°C 1 ADA4938-1ACPZ-RL −40°C to +85°C 1 ADA4938-1ACPZ-R7 −40°C to +85°C 1 ADA4938-2ACPZ-R2 −40°C to +85°C 1 ADA4938-2ACPZ-RL −40°C to +85°C ...
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... ADA4938-1/ADA4938-2 NOTES Rev Page ...
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... NOTES Rev Page ADA4938-1/ADA4938-2 ...
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... ADA4938-1/ADA4938-2 NOTES ©2007–2009 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D06592-0-10/09(A) Rev Page ...