ada4938-2 Analog Devices, Inc., ada4938-2 Datasheet
ada4938-2
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ada4938-2 Summary of contents
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... The part is specified to operate over the extended industrial temperature range of −40°C to +85°C. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 Fax: 781.461.3113 ©2007 Analog Devices, Inc. All rights reserved. ADA4938-2 18 +OUT1 17 V OCM1 16 – –V ...
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... Estimating the Output Noise Voltage ...................................... 19 e Impact of Mismatches in the Feedback Networks ......... 20 Calculating the Input Impedance of an Application Circuit 20 Input Common-Mode Voltage Range in Single-Supply Applications ................................................................................ 20 Setting the Output Common-Mode Voltage .......................... 21 Layout, Grounding, and Bypassing.............................................. 22 Outline Dimensions ....................................................................... 23 Ordering Guide .......................................................................... 23 Rev. PrB | Page ADA4938-2 ...
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... V OUT, dm IN, cm IN, cm Maximum ∆V ; single-ended output OUT ∆V /∆V ; ∆ MHz OUT, cm OUT, dm OUT, dm Rev. PrB | Page ADA4938 kΩ, unless otherwise noted Min Typ Max 1500 125 1300 800 4700 4 −112 −79 −102 −81 ...
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... ADA4938-2 Table ±OUT Performance OCM 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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... V OUT, dm IN, cm IN, cm Maximum ∆V ; single-ended output OUT ∆V /∆V ; ∆ OUT, cm OUT, dm OUT, dm Rev. PrB | Page ADA4938 kΩ, unless otherwise noted Min Typ Max 1500 125 1100 3900 4 −110 −79 −100 −79 TBD TBD 2 ...
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... ADA4938-2 Table ±OUT Performance OCM 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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... JEDEC standard 4-layer board. θ Unit JA 65 °C Figure 3. Maximum Power Dissipation vs. Temperature for a 4-Layer Board J ESD CAUTION Rev. PrB | Page ADA4938 the sum of the D ) times the quiescent S ). The power dissipated due to the load drive depends ...
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... ADA4938-2 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 7. Pin Function Descriptions Pin No. Mnemonic 1 −IN1 2 FB +OUT1 -OUT2 6 +IN2 7 −IN2 8 FB +OUT2 OCM2 12 +OUT2 13 −OUT2 14 PD2 −V 15 OCM1 18 +OUT1 19 −OUT1 20 PD1 21, 22 − -OUT1 24 +IN1 PIN 1 INDICATOR – ...
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... Figure 8. Large Signal Frequency Response for Various Gains 3 0 –3 –6 – + ±5V S – 100 FREQUENCY (MHz) Figure 9. Large Signal Response for Various Supplies 3 0 –3 –6 –9 –40°C +25°C +85°C – 100 FREQUENCY (MHz) ADA4938-2 1000 1000 1000 ...
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... ADA4938 –3 –6 –9 –12 – 1kΩ L – 100Ω 200Ω L – 100 FREQUENCY (MHz) Figure 11. Small Signal Frequency Response for Various Loads 0.1 V p-p OUT 3 0 –3 –6 – +3. – 100 FREQUENCY (MHz) Figure 12 ...
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... O, cm 1.2 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 –0.5 –0 1kΩ –0 100Ω –0 –0 200Ω –1 100 FREQUENCY (MHz) Figure 22. 0.1 dB Flatness Response for Various Loads 0.1 V p-p S OUT ADA4938-2 1000 = 402 Ω, F 1000 1000 ...
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... 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 23. Harmonic Distortion vs. Frequency and Supply Voltage –40 HD2 HD3 –50 HD2 HD3 –60 HD2 HD3 – ...
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... Figure 31. Output Balance vs. Frequency Figure 32. PSRR vs. Frequency Figure 33 S11 –5 S22 –10 –15 –20 –25 –30 –35 –40 –45 –50 –55 –60 – Figure 34. Return Loss (S11, S22) vs. Frequency Rev. PrB | Page ADA4938-2 CMRR vs. Frequency OUT 100 1000 FREQUENCY (MHz) ...
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... ADA4938-2 – 1kΩ 200Ω L – 100Ω L –60 –70 –80 –90 –100 –110 –120 1 10 FREQUENCY (MHz) Figure 35. SFDR vs. Frequency and Loads Figure 36. Noise Figure vs. Frequency –2 –4 –6 V × 3.16 – – ...
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... V p-p OUT –0.5 –1.0 –1.5 –2.0 = 0.1 V p-p OUT Rev. PrB | Page +85°C +25°C –40° 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 VOLTAGE (V) 3.0 2.5 2.0 1.5 1.0 0.5 0 TIME (1ns/DIV) Figure 45. Large Signal Transient Response 2.0 1.5 1.0 0.5 0 TIME (2ns/DIV) Figure 46. V Large Signal Transient Response O, cm ADA4938-2 3.6 3.8 4 ...
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... ADA4938-2 Figure 47. Settling Response 0. –3 – –3. –3. – – + +3. +3.7V O – 100 FREQUENCY (MHz) Figure 48. V Small Signal Frequency Response for Various 0.1 V p-p OUT Figure 49. HD3 ICPT vs. Frequency and V ...
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... Figure 52. Output Balance Circuit 200Ω 0.1uF 200Ω Filter + V OCM ADA4938-2 61.9 200Ω Ω – 412Ω 0.1uF 27.5Ω 200Ω Figure 53. Distortion Measurement Circuit Rev. PrB | Page ADA4938-2 1KΩ 50Ω 50Ω 412Ω Filter ...
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... ADA4938-2 OPERATIONAL DESCRIPTION DEFINITION OF TERMS Figure 54. 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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... 1/2 (4kTR ) 1 F1 1/2 (4kTR ) 1 F2 Rev. PrB | Page ADA4938 and feedback resistors ( modeled as a differential input, and the and i , appear between each input and nIN+ is the noise voltage density at the nCM 1 Figure 55. ADA4938 Noise Model Output Noise ...
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... Rev. PrB | Page Preliminary Technical Data ) between the inputs IN simply × IN + OCM ADA4938-2 V OUT – ⎛ ⎞ ⎜ ⎟ R ⎜ ⎟ ⎜ ⎟ − ...
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... Rev. PrB | Page ADA4938-2 input to a common-mode OCM pin is approximately 10 kΩ. If multiple OCM settings with both dual and single 5 V supplies. OCM Common-Mode Level at +IN, −IN ( − ...
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... ADA4938-2 LAYOUT, GROUNDING, AND BYPASSING As a high speed device, the ADA4938 is sensitive to the PCB environment in which it operates. Realizing its superior performance requires attention to the details of high speed PCB design. The first requirement is a solid ground plane that covers as much of the board area around the ADA4938 as possible. ...
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... Body, Very Thin Quad (CP-24-1) Dimensions shown in millimeters Package Description Package Option 24-Lead LFCSP_VQ CP-24-1 24-Lead LFCSP_VQ CP-24-1 24-Lead LFCSP_VQ CP-24-1 Rev. PrB | Page 0.60 MAX PIN 1 INDICATOR 2.25 EXPOSED 2.10 SQ PAD 1.95 (BOTTOM VIEW 0.25 MIN 2.50 REF Ordering Quantity 5,000 1,500 250 ADA4938-2 Branding ...