ADA4940-1 AD [Analog Devices], ADA4940-1 Datasheet
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ADA4940-1
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ADA4940-1 Summary of contents
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... SAR and sigma-delta (Σ-Δ) analog-to-digital converters (ADCs) with resolutions bits from MHz on only 1. quiescent current. The adjustable level of the output common-mode voltage allows the ADA4940-1/ ADA4940-2 to match the input common-mode voltage of multiple ADCs. The internal common-mode feedback loop provides exceptional output balance, as well as suppression of even-order harmonic distortion products ...
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... Ordering Guide .......................................................................... 29 Circuit Section ................................................................................ 23 Changes to Figure 71 ...................................................................... 25 Changes to Driving a High Precision ADC Section and Figure 73 ................................................................................... 26 Changed ADA4940-1 Example Section to ADA4940-1 LFCSP = +5 V Example Section ............................................................................. 27 S Changes to Ordering Guide .......................................................... 29 12/11—Rev Rev. A Changes to Features Section, General Description Section, Table 1 .................................................................................. 1 Replaced Figure 1 and Figure 2 ...
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... V dc OS, dm IN, cm IN, cm Each single-ended output MHz Ω, SFDR = −60 dBc MHz, ΔV /ΔV OUT, cm OUT, dm Rev Page ADA4940-1/ADA4940 −40°C to +125°C. MIN MAX Min Typ Max 260 220 ...
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... ADA4940-1/ADA4940 Performance OCM OUT, cm Table 4. Parameter V DYNAMIC PERFORMANCE OCM −3 dB Small Signal Bandwidth −3 dB Large Signal Bandwidth Slew Rate Input Voltage Noise Gain V CHARACTERISTICS OCM Input Common-Mode Voltage Range Input Resistance Offset Voltage Input Offset Voltage Drift Input Bias Current ...
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... V dc OS, dm IN, cm IN, cm Each single-ended output MHz Ω, SFDR = −60 dBc MHz, ΔV /ΔV OUT, cm OUT, dm Rev Page ADA4940-1/ADA4940 −40°C to +125°C. MIN MAX Min Typ Max 240 200 ...
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... ADA4940-1/ADA4940 Performance OCM OUT, cm Table 7. Parameter V DYNAMIC PERFORMANCE OCM −3 dB Small Signal Bandwidth −3 dB Large Signal Bandwidth Slew Rate Input Voltage Noise Gain V CHARACTERISTICS OCM Input Common-Mode Voltage Range Input Resistance Offset Voltage Input Offset Voltage Drift Input Bias Current ...
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... Package Type 8-Lead SOIC (Single)/4-Layer Board 16-Lead LFCSP (Single)/4-Layer Board 24-Lead LFCSP (Dual)/4-Layer Board MAXIMUM POWER DISSIPATION The maximum safe power dissipation in the ADA4940-1/ ADA4940-2 packages is limited by the associated rise in junction temperature ( the die. At approximately 150°C, ...
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... Negative Output for Load Connection. 12 DISABLE Disable Pin −V Negative Supply Voltage. S Exposed Connect the exposed pad to −V paddle (EPAD) ground. OCM Table 12. ADA4940-1 Pin Function Descriptions (8-Lead SOIC) Pin No Rev Page Data Sheet – ...
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... Output Common-Mode Voltage 2. Positive Output 2. Negative Output 2. Disable Pin 2. Negative Supply Voltage 2. Output Common-Mode Voltage 1. Positive Output 1. Negative Output 1. Disable Pin 1. Negative Supply Voltage 1. Negative Output Feedback Pin 1. Positive Input Summing Node 1. Connect the exposed pad to −V Rev Page ADA4940-1/ADA4940-2 or ground. S ...
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... ADA4940-1/ADA4940-2 TYPICAL PERFORMANCE CHARACTERISTICS T = 25° ±2 kΩ test circuits 1kΩ –1 = 200Ω –2 L – –4 –5 = 200Ω –6 L –7 – 0.1V p-p OUT, dm –9 0 FREQUENCY (MHz) Figure 7 ...
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... Levels (LFCSP) Figure 17. Large Signal Frequency Response at Various V OCM = –1V = +1V 100 1000 (SOIC) Figure 18. Small Signal Frequency Response for Various Packages and Loads OCM Rev Page ADA4940-1/ADA4940 –1 –2 –3 –4 –5 –6 –7 –8 ...
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... ADA4940-1/ADA4940 2pF COM1 COM2 1pF –1 COM1 COM2 0.5pF –2 COM1 COM2 0pF –3 COM1 COM2 –4 –5 –6 – 0pF DIFF – 0.1V p-p OUT – FREQUENCY (MHz) Figure 19. Small Signal Frequency Response for Various Capacitive Loads (LFCSP) 0 ...
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... HD2 200Ω Figure 29. Harmonic Distortion vs. Frequency for Various Loads (SOIC) HD2 ±2. Figure 30. Harmonic Distortion vs. Frequency for Various Supplies (SOIC) Rev Page ADA4940-1/ADA4940-2 – p-p OUT, dm –30 HD3 –40 HD3 –50 –60 –70 –80 HD2 – ...
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... ADA4940-1/ADA4940-2 – p-p OUT, dm –30 –40 –50 –60 –70 –80 SOIC 200Ω L –90 SOIC 1kΩ L –100 –110 LFCSP: R –120 LFCSP –130 0.01 0.1 1 FREQUENCY (MHz) Figure 31. Spurious-Free Dynamic Range vs. Frequency 200 Ω and R = 1kΩ – p-p OUT, dm – ...
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... Rev Page ADA4940-1/ADA4940 p-p OUT, dm CHANNEL 1 TO CHANNEL 2 CHANNEL 2 TO CHANNEL 1 0 FREQUENCY (MHz) Figure 40. Crosstalk vs. Frequency, ADA4940-2 90 –PSRR +PSRR 0.1 ...
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... ADA4940-1/ADA4940 OUT × –2 –4 –6 –8 0 100 200 300 400 500 600 TIME (ns) Figure 43. Output Overdrive Recovery 100 100 1k 10k FREQUENCY (Hz) Figure 44. Voltage Noise Spectral Density, Referred to Input 1.50 1.25 –OUT ICM 1.00 0. ...
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... Figure 51. Small Signal Transient Response for Various Capacitive Loads (LFCSP) 150 Figure 52. Large Signal Transient Response for Various Gains and Loads = ±3.5V = 0pF = 0.5pF = 1pF = 2pF 150 Figure 54. Large Signal Transient Response for Various Capacitive Loads Rev Page ADA4940-1/ADA4940-2 1.5 1.0 0 1kΩ –0 200Ω 1kΩ ...
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... ADA4940-1/ADA4940-2 100 –20 –40 –60 – 0.1V p-p OUT, dm –100 100 110 120 130 140 150 TIME (ns) Figure 55. Small Signal Transient Response for Various Packages, C 100 ±2. ±1. –20 –40 –60 – ...
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... Figure 59. Equivalent Basic Test Circuit 1kΩ +2.5V 1kΩ 475Ω ADA4940-1/ V 52.3Ω OCM ADA4940-2 1kΩ 475Ω –2.5V 1kΩ Figure 60. Test Circuit for Distortion Measurements Rev Page ADA4940-1/ADA4940-2 NETWORK ANALYZER INPUT 475Ω 50Ω 54.9Ω 54.9Ω 50Ω 475Ω 100Ω 50Ω HP 2:1 DUAL FILTER LP 54.9Ω ...
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... ADA4940-1/ADA4940-2 TERMINOLOGY DEFINITION OF TERMS – + ADA4840-1/ +V OCM ADA4940 –IN – +FB Figure 61. Circuit Definitions Differential Voltage Differential voltage refers to the difference between two node voltages. For example, the differential output voltage (or equivalently, output differential mode voltage) is defined as ...
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... Note that the differential amplifier’s summing junction input voltages, +IN and −IN, are set by both the output voltages and R F the input voltages. –OUT V OCM +OUT R F Rev Page ADA4940-1/ADA4940 − − IN OUT − − ...
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... V V nRG1 nRF1 nIN ADA4940-1/ nIN i nIN– ADA4940-2 V OCM nRG2 nRF2 Figure 63. ADA4940-1/ADA4940-2 Noise Model 2 is the circuit noise gain β β β G2 and are the feedback factors ...
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... ADA4940-1/ OCM ADA4940-2 –D IN – ADA4940-1/ADA4940-2 Configured for Balanced (Differential) Inputs + OCM ADA4940-1/ ADA4940 – ADA4940-1/ADA4940-2 Configured for Unbalanced (Single-Ended) Input . G1 RTI (nV/√Hz) 11.2 7.5 6 OUT OUT, dm ...
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... This is within the tolerance of the resistors change to the feedback resistor, R INPUT COMMON-MODE VOLTAGE RANGE T in the upper feedback G The ADA4940-1/ADA4940-2 shifted down by approximately 1 V drivers with centered input ranges, such as the ADA4939-x. The ) TS downward-shifted input common-mode range is especially is the Thevenin ...
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... V above the negative supply rail. See Table 5 and Table 8 for the threshold limits. The DISABLE pin features an internal pull-up network that enables the amplifier for normal operation. The ADA4940-1/ DISABLE pin can be left floating (that is, no ADA4940-2 ...
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... V OCM ADA4940-1 33Ω +OUT –IN +FB R2 –1V Figure 73. ADA4940-1 (LFCSP) Driving the Rev Page ADA4940-1 output swings between 0 ADA4940-1 output and the ADC provides single-pole, is used to regulate the +6 V supply which ends pin. 0 –20 –40 –60 – ...
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... ADA4940-1/ADA4940-2 sensitive to the PCB environment in which they operate. Realizing their superior performance requires attention to the details of high speed PCB design. ADA4940-1 LFCSP EXAMPLE The first requirement is a solid ground plane that covers as much of the board area around the ADA4940-1 However, clear the area near the feedback resistors (R ...
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... ADA4940-1/ADA4940-2 OUTLINE DIMENSIONS PIN 1 INDICATOR 12° MAX 1.00 0.85 0.80 SEATING PLANE 0.25 (0.0098) 0.10 (0.0040) COPLANARITY 3.00 0.60 MAX BSC SQ 0.45 12 2.75 TOP BSC SQ VIEW 9 0.50 BSC 1.50 REF 0.80 MAX 0.65 TYP 0.05 MAX 0.02 NOM 0.30 0.20 REF 0.23 0.18 * COMPLIANT TO JEDEC STANDARDS MO-220-VEED-2 EXCEPT FOR EXPOSED PAD DIMENSION. Figure 77. 16-Lead Lead Frame Chip Scale Package [LFCSP_VQ × ...
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... ADA4940-1ACPZ-R7 −40°C to +125°C ADA4940-1ACP-EBZ ADA4940-1ARZ −40°C to +125°C ADA4940-1ARZ-RL −40°C to +125°C ADA4940-1ARZ-R7 −40°C to +125°C ADA4940-1AR-EBZ ADA4940-2ACPZ-R2 −40°C to +125°C ADA4940-2ACPZ-RL −40°C to +125°C ADA4940-2ACPZ-R7 −40°C to +125°C ...
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... ADA4940-1/ADA4940-2 NOTES Rev Page Data Sheet ...
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... Data Sheet NOTES Rev Page ADA4940-1/ADA4940-2 ...
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... ADA4940-1/ADA4940-2 NOTES ©2011–2012 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D08452-0-3/12(B) Rev Page Data Sheet ...