ada4927 Analog Devices, Inc., ada4927 Datasheet
ada4927
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ada4927 Summary of contents
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... ADA4927 make it well suited for a wide variety of data acquisition and signal processing applications. The ADA4927-1 is available in a Pb-free × 16-lead LFCSP, and the ADA4927-2 is available in a Pb-free × 24-lead LFCSP. The pinouts are optimized to facilitate printed circuit board (PCB) layout and to minimize distortion. They are specified to operate over the − ...
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... ADA4927-1/ADA4927-2 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagrams ............................................................. 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 ±5 V Operation ............................................................................. Operation ............................................................................. 5 Absolute Maximum Ratings ............................................................ 7 Thermal Resistance ...................................................................... 7 Maximum Power Dissipation ..................................................... 7 ESD Caution .................................................................................. 7 Pin Configurations and Function Descriptions ........................... 8 Typical Performance Characteristics ............................................. 9 Test Circuits ..................................................................................... 15 Theory of Operation ...................................................................... 16 REVISION HISTORY 10/08— ...
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... OUT p-p, 100 MHz OUT MHz 70.1 MHz OUT 140 MHz 140.1 MHz OUT 100 kHz 100 kHz 100 MHz, ADA4927 OCM variation MIN MAX variation MIN MAX Differential ...
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... ADA4927-1/ADA4927 Performance OCM OUT, cm Table 2. Parameter V DYNAMIC PERFORMANCE OCM Small Signal −3 dB Bandwidth Slew Rate Input Voltage Noise (RTI) V INPUT CHARACTERISTICS OCM Input Voltage Range Input Resistance Input Offset Voltage V CMRR OCM Gain General Performance Table 3. Parameter POWER SUPPLY ...
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... V p-p, 100 MHz OUT MHz 70.1 MHz p OUT 140 MHz 140.1 MHz p OUT 100 kHz 100 kHz 100 MHz, ADA4927 OCM variation MIN MAX variation MIN MAX Differential ...
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... ADA4927-1/ADA4927 Performance OCM OUT, cm Table 5. Parameter V DYNAMIC PERFORMANCE OCM Small signal −3 dB Bandwidth Slew Rate Input Voltage Noise (RTI) V INPUT CHARACTERISTICS OCM Input Voltage Range Input Resistance Input Offset Voltage V CMRR OCM Gain General Performance Table 6. Parameter POWER SUPPLY ...
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... LFCSP (Exposed Pad) 24-Lead LFCSP (Exposed Pad) MAXIMUM POWER DISSIPATION The maximum safe power dissipation in the ADA4927 package is limited by the associated rise in junction temperature (T the die. At approximately 150°C, which is the glass transition temperature, the plastic changes its properties. Even temporarily ...
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... Negative Output for Load Connection 12 Power-Down Pin −V Negative Supply Voltage S 17 (EPAD) Exposed Connect the exposed pad to any Pad (EPAD) plane between and including +V and − Table 10. ADA4927-2 Pin Function Descriptions Pin No 15 ...
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... R = 301 Ω 56.2 Ω (when used 10k 1k 10k 1k 10k Figure 12. Large Signal Frequency Response for Various Temperatures Rev Page ADA4927-1/ADA4927 kΩ, unless otherwise noted p-p OUT dm 0 –3 – 301Ω – 10 442Ω ...
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... ADA4927-1/ADA4927 100mV p-p OUT dm 0 –3 – 200Ω L – 1kΩ L – 100 FREQUENCY (MHz) Figure 13. Small Signal Frequency Response for Various Loads 100mV p-p OUT dm 0 –3 – –4V OCM V = –3.5V OCM –9 OCM V = +3.5V OCM V = +4V OCM – ...
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... HD2, 10MHz –110 HD3, 10MHz –120 –4 0.6 0.8 1.0 1.2 Figure 24. Harmonic Distortion vs. V Rev Page ADA4927-1/ADA4927 p-p OUT dm HD2 HD3 HD2 HD3 HD2 HD3 100 FREQUENCY (MHz p-p ...
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... INPUT AMP2 TO OUTPUT AMP1 –50 INPUT AMP1 TO OUTPUT AMP2 –60 –70 –80 –90 –100 –110 –120 –130 –140 0 100 FREQUENCY (MHz) Figure 29. Crosstalk vs. Frequency for ADA4927-2 – 200Ω –30 –40 –50 –60 – ±5V, –PSRR S – ±5V, +PSRR S – ...
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... –5 –10 1k 0.1 Figure 35. Closed-Loop Output Impedance Magnitude vs. Frequency –5 – 10M 100M Rev Page ADA4927-1/ADA4927-2 MAGNITUDE PHASE 1k 10k 100k 1M 10M 100M 1G 10G FREQUENCY (Hz ± ± ±2.5V ...
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... ADA4927-1/ADA4927 –10 –20 –30 –40 –50 – TIME (ns) Figure 37. Small Signal Pulse Response –10 –20 –30 –40 –50 – TIME (ns) Figure 38. V Small Signal Pulse Response OCM 1.2 1.0 0.8 0.6 0.4 0.2 0 –0.2 – ...
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... FILTER 56.2Ω V ADA4927 OCM 0.1µF 301Ω 25.5Ω 0.1µF –5V 301Ω Figure 45. Test Circuit for Distortion Measurements Rev Page ADA4927-1/ADA4927-2 1kΩ DIFFERENTIAL NETWORK ANALYZER INPUT 50Ω DIFFERENTIAL NETWORK ANALYZER INPUT 50Ω 200Ω 50Ω 442Ω HP ...
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... Moreover, the ADA4927 OCM uses a current feedback architecture. Like a traditional current feedback op amp, the ADA4927 relies on high open-loop trans- impedance, T(s), and negative current feedback to force the outputs to the desired voltages. The ADA4927 behaves much like a standard current feedback op amp and facilitates single- ended-to-differential conversions, common-mode level shifting, and amplifications of differential signals ...
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... F1 nRF1 Feedback Resistor nRF2 ESTIMATING THE OUTPUT NOISE VOLTAGE The differential output noise of the ADA4927 can be estimated using the noise model in Figure 47. The input-referred noise voltage density, v noise currents, i ground. The output voltage due the noise gain, G nIN ...
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... For balanced differential input signals, as shown in Figure 48, the input impedance (R (+D IN input (including OCM Figure 48. The ADA4927 Configured for Balanced (Differential) Inputs input OCM Rev Page Differential Output Noise Density (nV/√Hz) 8.1 18.6 29 ...
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... R G Terminating a Single-Ended Input This section deals with how to properly terminate a single- ended input to the ADA4927 with a gain 348 Ω. An example using an input source with a terminated G output voltage p-p and a source resistance of 50 Ω illustrates the four simple steps that must be followed ...
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... R TS 26.7Ω – 357Ω . This ac coupling blocks the flow of the dc common- G pin of the ADA4927 is internally biased with a voltage OCM ) + (− pin sources and sinks current, depending OCM input is driven by a low impedance voltage source. OCM input to a common-mode OCM pin is approximately 10 kΩ ...
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... The ADA4927 is generally enabled by pulling the power-down pin to the positive supply. See the Specifications tables for the specific voltages required to assert and deassert the power- down feature ...
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... ADA4927-1/ADA4927-2 LAYOUT, GROUNDING, AND BYPASSING As a high speed device, the ADA4927 is sensitive to the PCB environment in which it operates. Realizing its superior performance requires attention to the details of high speed PCB design. This section shows a detailed example of how the ADA4927-1 was addressed. The first requirement is a solid ground plane that covers as much of the board area around the ADA4927-1 as possible ...
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... SIGNAL GENERATOR 0.1µF Figure 58. ADA4927 Driving an AD9445 ADC with AC-Coupled Input and Output In this example, the signal generator has p-p symmetric, ground-referenced bipolar output when terminated in 50 Ω. The V and left floating such that the internal divider sets the output common-mode voltage nominally at midsupply ...
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... ADA4927-1YCPZ-R7 −40°C to +105°C 1 ADA4927-2YCPZ-R2 −40°C to +105°C 1 ADA4927-2YCPZ-RL −40°C to +105°C 1 ADA4927-2YCPZ-R7 −40°C to +105° RoHS Compliant Part. ©2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. ...