ada4950-1 Analog Devices, Inc., ada4950-1 Datasheet
ada4950-1
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ada4950-1 Summary of contents
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... Figure 3. Harmonic Distortion vs. Frequency at Various Supplies The ADA4950-x is available in a Pb-free × 3 mm, 16-lead LFCSP (ADA4950-1, single Pb-free × 4 mm, 24-lead LFCSP (ADA4950-2, dual). The pinout has been optimized to facilitate PCB layout and minimize distortion. The ADA4950-1/ ADA4950-2 are specified to operate over the −40°C to +105°C temperature range ...
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... ADA4950-1/ADA4950-2 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 ..................................................................................... 16 Terminology .................................................................................... 17 REVISION HISTORY 5/09— ...
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... L, dm ∆V /∆V , ∆ p-p, 1 MHz; OUT, cm OUT, dm OUT, dm see Figure 50 for output balance test circuit Gain = 1 Gain = 2 Gain = 3 Rev Page ADA4950-1/ADA4950 kΩ, unless otherwise noted. All specifications L, dm Min Typ Max 750 350 210 230 2900 9 20 − ...
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... ADA4950-1/ADA4950 Performance OCM OUT, cm Table 2. Parameter V DYNAMIC PERFORMANCE OCM −3 dB Small-Signal Bandwidth −3 dB Large-Signal Bandwidth Slew Rate Input Voltage Noise (Referred to Input) V INPUT CHARACTERISTICS OCM Input Voltage Range Input Resistance Input Offset Voltage V CMRR OCM Gain General Performance Table 3. ...
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... L, dm ∆V /∆V , ∆ p-p, 1 MHz; OUT, cm OUT, dm OUT, dm see Figure 50 for output balance test circuit Gain = 1 Gain = 2 Gain = 3 Rev Page ADA4950-1/ADA4950 kΩ, unless otherwise noted. All specifications Min Typ Max 770 320 220 160 2200 10 19 −108 − ...
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... ADA4950-1/ADA4950 Performance OCM OUT, cm Table 5. Parameter V DYNAMIC PERFORMANCE OCM −3 dB Small-Signal Bandwidth −3 dB Large-Signal Bandwidth Slew Rate Input Voltage Noise (Referred to Input) V INPUT CHARACTERISTICS OCM Input Voltage Range Input Resistance Input Offset Voltage V CMRR OCM Gain General Performance Table 6. ...
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... EIA/JESD51-7. Table 8. Thermal Resistance Package Type ADA4950-1, 16-Lead LFCSP (Exposed Pad) ADA4950-2, 24-Lead LFCSP (Exposed Pad) MAXIMUM POWER DISSIPATION The maximum safe power dissipation in the ADA4950-x package is limited by the associated rise in junction temperature (T the die. At approximately 150° ...
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... ADA4950-1 +INA 2 –INA 3 TOP VIEW (Not to Scale) –INB 4 NOTES 1. SOLDER THE EXPOSED PADDLE ON THE BACK OF THE PACKAGE TO A GROUND PLANE POWER PLANE. Figure 5. ADA4950-1 Pin Configuration Table 9. ADA4950-1 Pin Function Descriptions Pin No. Mnemonic 1 +INB 2 +INA 3 −INA 4 −INB ...
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... 53.6 Ω (when used 1000 1000 Figure 11. Large-Signal Frequency Response for Various Supplies 1000 Figure 12. Large-Signal Frequency Response for Various Temperatures Rev Page ADA4950-1/ADA4950 kΩ, unless otherwise noted. Refer to Figure p-p 1 OUT 53.6Ω ...
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... ADA4950-1/ADA4950 100mV p-p OUT – 1kΩ 200Ω –2 L –3 –4 –5 –6 –7 – 100 FREQUENCY (MHz) Figure 13. Small-Signal Frequency Response at Various Loads 100mV p-p 1 OUT – –2.5VDC OCM –2 OCM V = +2.5VDC OCM – ...
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... Figure 24. Harmonic Distortion vs. Frequency at Various Gains Rev Page ADA4950-1/ADA4950-2 0 p-p OUT, dm 0.4 0.3 0.2 0.1 0 ADA4950- 1kΩ L ADA4950- 200Ω L ADA4950-2, AMP 1kΩ L ADA4950-2, AMP 200Ω L ADA4950-2, AMP 1kΩ L ADA4950-2, AMP 200Ω ...
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... ADA4950-1/ADA4950-2 – p-p OUT, dm –50 –60 HD2, ±5V HD3, ±5V –70 HD2, ±2.5V HD3, ±2.5V –80 –90 –100 –110 –120 –130 –140 0.1 1 FREQUENCY (MHz) Figure 25. Harmonic Distortion vs. Frequency at Various Supplies – p-p OUT, dm –40 –50 HD2 AT 10MHz –60 HD3 AT 10MHz HD2 AT 30MHz – ...
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... Figure 34. Open-Loop Gain and Phase vs. Frequency 0 –20 –40 –60 –80 –100 –120 1 1000 0 –20 –40 –60 –80 –100 –120 –140 1 1G Rev Page ADA4950-1/ADA4950-2 GAIN PHASE 10k 100k 1M 10M 100M 1G FREQUENCY (Hz 200Ω 100mV p-p IN, dm PSRR+ PSRR– 10 100 FREQUENCY (MHz) Figure 35 ...
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... ADA4950-1/ADA4950-2 0 INPUT SINGLE-ENDED, 50Ω LOAD TERMINATION OUTPUT DIFFERENTIAL, 100Ω SOURCE TERMINATION S11: SINGLE-ENDED-TO-SINGLE-ENDED –10 S22: DIFFERENTIAL-TO-DIFFERENTIAL R = 200Ω 100mV p-p –20 IN, dm –30 S11 –40 S22 –50 – FREQUENCY (MHz) Figure 37. Return Loss ( vs. Frequency 11 22 ...
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... V 0.4 5 0.3 4 0.2 0 –0.1 –0.2 1 –0.3 0 –0.4 –0.5 – Rev Page ADA4950-1/ADA4950 0pF 0.9pF 1.8pF 2.7pF TIME (ns TIME (ns) Figure 47. V Large-Signal Pulse Response OCM = +1V DC ...
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... ADA4950-1/ADA4950-2 TEST CIRCUITS DC-COUPLED SOURCE V IN DIFFERENTIAL NETWORK ANALYZER SOURCE 49.9Ω 49.9Ω DC-COUPLED SOURCE 50Ω LOW-PASS FILTER V IN 25.5Ω 250Ω 500Ω NC 500Ω 50Ω 53.6Ω V ADA4950-x OCM 500Ω 0.1µF 25.5Ω 250Ω 500Ω NC Figure 49. Equivalent Basic Test Circuit +5V 250Ω ...
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... Any imbalances in amplitude or phase produce an undesired common-mode signal at the amplifier output. Output balance error is defined as the magnitude of the output common-mode voltage divided by the magnitude of the output differential mode voltage. Output Rev Page ADA4950-1/ADA4950 )/2 +OUT −OUT Δ V ...
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... ADA4950-1/ADA4950-2 THEORY OF OPERATION The ADA4950-x differs from conventional op amps in that it has two outputs whose voltages move in opposite directions and an additional input Like an op amp, it relies on high open-loop OCM gain and negative feedback to force these outputs to the desired voltages. The ADA4950-x behaves much like a standard voltage ...
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... (4kTR ) 1 1/2 (4kTR ) 1 F2 Rev Page ADA4950-1/ADA4950-2 Ω 500 = 3 Ω Ω || 250 depend on G nIN− by the noise gain, G nIN equation that follows Table 13). The noise pin When the feedback OCM nCM is common mode. Each of the four ...
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... ADA4950-1/ADA4950-2 Table 12. Differential Input, DC-Coupled Nominal Linear Gain R (Ω 500 2 500 3 500 Table 13. Single-Ended, Ground-Referenced Input, DC-Coupled, R Nominal Linear Gain R (Ω 500 2 500 3 500 || Similar to the case of a conventional op amp, the output noise voltage densities can be estimated by multiplying the input- referred terms at +INx and − ...
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... The desired differential output in this example p-p because the terminated input signal p-p and the closed- loop gain = 1. The actual differential output voltage, however, is equal to (1.03 V p-p)(500/525.5) = 0.98 V p-p. Rev Page ADA4950-1/ADA4950-2 in the upper feedback G in the lower loop due to the G in the lower loop ...
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... ADA4950-1/ADA4950-2 INPUT COMMON-MODE VOLTAGE RANGE The ADA4950-x input common-mode voltage range is shifted down by approximately one contrast to other ADC BE drivers with centered input ranges such as the ADA4939-x. The downward-shifted input common-mode range is especially suited to dc-coupled, single-ended-to-differential, and single- supply applications. ...
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... PCB traces close together, and twist any differential wiring to minimize loop area. Doing this reduces radiated energy and makes the circuit less susceptible to interference. 1.30 0.80 Figure 61. Recommended PCB Thermal Attach Pad (Dimensions in Millimeters) 1.30 0.30 PLATED VIA HOLE Rev Page ADA4950-1/ADA4950-2 1.30 0.80 ...
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... UNIPOLAR SIGNAL 0V SOURCE 0.1µF Figure 63. ADA4950-1 Driving an AD9245 ADC with Unipolar DC-Coupled Input and Output, Gain = 2 Because the inputs are dc-coupled, dc common-mode current flows in the feedback loops, and a nominal dc level of 0. AD9245 ADC, present at the amplifier input terminals. A fraction of the output signal is also present at the input terminals as a common-mode signal ...
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... Figure 65. 24-Lead Lead Frame Chip Scale Package [LFCSP_VQ × Body, Very Thin Quad (CP-24-1) Dimensions shown in millimeters Package Description Package Option 16-Lead LFCSP_VQ CP-16-2 16-Lead LFCSP_VQ CP-16-2 16-Lead LFCSP_VQ CP-16-2 24-Lead LFCSP_VQ CP-24-1 24-Lead LFCSP_VQ CP-24-1 24-Lead LFCSP_VQ CP-24-1 Rev Page ADA4950-1/ADA4950-2 0.50 0.40 0.30 PIN 1 INDICATOR * 1. 1.30 SQ 1.15 PAD 4 5 0.25 MIN PIN 1 INDICATOR ...
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... ADA4950-1/ADA4950-2 NOTES Rev Page ...
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... NOTES Rev Page ADA4950-1/ADA4950-2 ...
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... ADA4950-1/ADA4950-2 NOTES ©2009 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D07957-0-5/09(0) Rev Page ...