ada4937-2 Analog Devices, Inc., ada4937-2 Datasheet
ada4937-2
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ada4937-2 Summary of contents
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... PCB layout and minimize distortion. The ADA4937-1 is specified to operate over the −40°C to +105°C temperature range, and the ADA4937-2 operates over −40°C to +85°C; both operate at 3.3 V and 5 V supplies. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. ...
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... Pin Configuration and Function Descriptions............................. 8 Typical Performance Characteristics ............................................. 9 Test Circuits..................................................................................... 16 Operational Description................................................................ 17 Definition of Terms.................................................................... 17 REVISION HISTORY 11/07—Rev Rev. A Added the ADA4937-2 ......................................................Universal Changes to Features.......................................................................... 1 Changes to Specifications ................................................................ 3 Changes to Figure 4.......................................................................... 7 Changes to Typical Performance Characteristics......................... 9 Inserted Figure 44........................................................................... 15 Added the Terminating a Single-Ended Input Section ............. 19 Changes to Table 10 and Table 11 ...
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... Slew Rate Overdrive Recovery Time NOISE/HARMONIC PERFORMANCE Second Harmonic Third Harmonic IMD Voltage Noise (RTI) Input Current Noise Noise Figure Crosstalk (ADA4937-2) INPUT CHARACTERISTICS Offset Voltage Input Bias Current Input Offset Current Input Resistance Input Capacitance Input Common-Mode Voltage CMRR OUTPUT CHARACTERISTICS ...
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... ADA4937-1/ADA4937 ±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 per Amplifier ...
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... Slew Rate Overdrive Recovery Time NOISE/HARMONIC PERFORMANCE Second Harmonic Third Harmonic IMD Voltage Noise (RTI) Input Current Noise Noise Figure Crosstalk (ADA4937-2) 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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... ADA4937-1/ADA4937 ±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 per Amplifier ...
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... JA 95 °C/W 1.0 67 °C/W 0 Figure 4. Maximum Power Dissipation vs. Temperature for a 4-Layer Board ESD CAUTION Rev Page ADA4937-1/ADA4937 the sum of the D ) times the quiescent current ( ADA4937-2 ADA4937-1 0 –40 –30 –20 – AMBIENT TEMPERATURE (° ...
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... Figure 5. ADA4937-1 Pin Configuration Table 7. ADA4937-1 Pin Function Descriptions Pin No. Mnemonic 1 −FB 2 +IN 3 − OCM 10 +OUT 11 −OUT −V S Table 8. ADA4937-2 Pin Function Descriptions Pin No. Mnemonic 1 −IN1 2 +FB1 −FB2 6 +IN2 7 −IN2 8 +FB2 OCM2 12 +OUT2 13 − ...
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... V = 100 mV p-p OUT p- / 61.9 Ω, R OCM S T 1000 1000 1000 Figure 12. Large Signal Frequency Response for Various Temperatures Rev Page ADA4937-1/ADA4937 200 Ω kΩ, unless otherwise –3 –6 –9 – + 200Ω ...
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... ADA4937-1/ADA4937 1kΩ 100Ω 200Ω –3 –6 – 100 FREQUENCY (MHz) Figure 13. Small Signal Frequency Response for Various Loads 100 mV p-p OUT –3 –6 –9 – 3.3V + 200Ω 3.3V + 402Ω ...
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... OCM V = 3.9V OCM 0 –3 –6 –9 – 100 FREQUENCY (MHz) Figure 19. Small Signal Frequency Response for Various V OCM 1 1kΩ, ADA4937-1 1 100Ω, ADA4937-1 1 1kΩ, ADA4937 100Ω, ADA4937-2 L 1.1 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 –0.1 –0.2 –0.3 –0.4 –0 100 FREQUENCY (MHz) Figure 20. 0.1 dB Flatness Response for Various Loads – ...
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... ADA4937-1/ADA4937-2 –30 HD2 10MHz HD3 10MHz –40 HD2 75MHz HD3 75MHz –50 –60 –70 –80 –90 –100 –110 –120 1.0 1.5 2.0 2.5 V (V) OCM Figure 25. Harmonic Distortion vs. V –40 HD2 30MHz HD3 30MHz HD2 75MHz –50 HD3 75MHz –60 –70 –80 –90 –100 1 ...
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... Figure 35. Overdrive Recovery Time (Pulse Input –1 –2 –3 –4 –5 0 100 Figure 36. Overdrive Amplitude Characteristics (Triangle Wave Input) Rev Page ADA4937-1/ADA4937 100 FREQUENCY (MHz) Figure 34. Noise Figure vs. Frequency V × 3. OUT, dm TIME (4ns/DIV) V × ...
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... ADA4937-1/ADA4937 +25° 0°C 15 –40° 1.0 1.1 1.2 1.3 1.4 1.5 1.6 POWER-DOWN VOLTAGE (V) Figure 37. Supply Current vs. PD for Various Temperatures 0.20 0.15 0.10 0.05 0 –0.05 –0.10 –0.15 –0.20 TIME (1ns/DIV) Figure 38. Small Signal Pulse Response 2.60 2.58 2.56 2.54 2.52 2.50 2.48 2.46 2.44 2.42 2.40 TIME (2ns/DIV) Figure 39. Small Signal V Pulse Response OCM +105°C +55° ...
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... INPUT2, OUTPUT1 –60 –70 –80 –90 –100 INPUT1, OUTPUT2 –110 –120 –130 –140 0 100 FREQUENCY (MHz) Figure 44. Crosstalk vs. Frequency for ADA4937-2 100 100 Figure 45. Voltage Spectral Noise Density, RTI 1000 Rev Page ADA4937-1/ADA4937-2 1k 10k 100k 1M 10M FREQUENCY (Hz) ...
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... ADA4937-1/ADA4937-2 TEST CIRCUITS 50Ω 200Ω 5V 50Ω 200Ω ADA4937 IN 61.9Ω OCM 200Ω 27.5Ω 200Ω Figure 46. Equivalent Basic Test Circuit 200Ω 5V 50Ω 200Ω ADA4937 IN 61.9Ω OCM 200Ω 27.5Ω 200Ω ...
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... Figure 47). By this definition, output balance is the magnitude of the output common-mode voltage divided by the magnitude of the output differential mode voltage. Output Rev Page ADA4937-1/ADA4937 )/2 +OUT −OUT V ...
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... ADA4937-1/ADA4937-2 THEORY OF OPERATION The ADA4937 differs from conventional op amps in that it has two outputs whose voltages move in opposite directions. Like an op amp, it relies on open-loop gain and negative feedback to force these outputs to the desired voltages. The ADA4937 behaves much like a standard voltage feedback op amp, which ...
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... ADA4937. Using a simple example with an input source and a source resistor of 50 Ω, four simple steps must be followed. 1. The input impedance must be calculated using the formula R ) between the inputs . G Rev Page ADA4937-1/ADA4937 ADA4937 + +IN +D ...
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... ADA4937-1/ADA4937 order for the source termination Ω, the termi- nation resistor ( calculated using R T which makes R equal to 61.9 Ω. T 200Ω 50Ω 50Ω 200Ω 61.9Ω V ADA4937 OCM 200Ω 200Ω Figure 54. Adding Termination Resistor R 3 ...
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... Differential Output Noise Density (nV/√Hz) IN, dm 400 5.8 400 9.6 254 12.1 161 16 Ω (Ω) R (Ω) R (Ω 61.9 267 226 60.4 301 228 66.5 205 155 76.8 138 111 Rev Page ADA4937-1/ADA4937 kΩ; See Figure 52 L Differential Output Noise Density (nV/√Hz) 5.5 8.6 10.1 12.2 ...
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... ADA4937-1/ADA4937-2 LAYOUT, GROUNDING, AND BYPASSING As a high speed device, the ADA4937 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 ADA4937-1 was addressed. The first requirement is a solid ground plane that covers as much of the board area around the ADA4937-1 as possible ...
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... V ADA4937 OCM 24.3Ω 30nH 226Ω 0.1µF 200Ω Figure 61. ADA4937 Driving an AD9445, a 14-Bit, 105 MSPS ADC Rev Page ADA4937-1/ADA4937-2 pin of the ADA4937 is left floating, OCM 5V (A) 3.3V (A) 3.3V (D) AVDD2 AVDD1 DRVDD VIN– AD9445 BUFFER T/H 47pF ...
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... ADA4937-1/ADA4937-2 The circuit in Figure 63 shows a simplified front-end connection for an ADA4937 driving an AD9246, 14-bit, 125 MSPS ADC. The AD9246 achieves its optimum performance when driven differentially. The ADA4937 performs the single-ended-to- differential conversion, eliminating the need for a transformer to drive the ADC. ...
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... ADC inputs. 453Ω 3.3V 56nH 33Ω 200Ω ADA4937 OCM 10pF 30pF 33Ω 56nH 226Ω 453Ω Figure 64. ADA4937 Driving an AD9230, a 12-Bit, 250 MSPS ADC Rev Page ADA4937-1/ADA4937-2 1.8V AVDD DRVDD VIN– D11 TO AD9230 D0 VIN+ AGND CML pin is OCM ...
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... ADA4937-1YCPZ-RL −40°C to +105°C 1 ADA4937-1YCPZ-R7 −40°C to +105°C 1 ADA4937-2YCPZ-R2 −40°C to +85°C 1 ADA4937-2YCPZ-RL −40°C to +85°C 1 ADA4937-2YCPZ-R7 −40°C to +85° RoHS Compliant Part. 3.00 0.60 MAX BSC SQ 0.45 2.75 TOP BSC SQ VIEW 0.50 BSC 1.50 REF 0.80 MAX ...
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... NOTES Rev Page ADA4937-1/ADA4937-2 ...
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... ADA4937-1/ADA4937-2 NOTES ©2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D06591-0-11/07(A) Rev Page ...