AD8108AST Analog Devices Inc, AD8108AST Datasheet
AD8108AST
Specifications of AD8108AST
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AD8108AST Summary of contents
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EATURES 8 × 8 high speed nonblocking switch arrays AD8108 AD8109 Serial or parallel programming of switch array Serial data out allows daisy-chaining of multiple 8 × 8 arrays to create larger switch arrays ...
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AD8108/AD8109 TABLE OF CONTENTS AD8108/AD8109—Specifications ................................................. 3 Timing Characteristics (Serial) .................................................. 5 Timing Characteristics (Parallel) ............................................... 6 Absolute Maximum Ratings............................................................ 8 Maximum Power Dissipation ..................................................... 8 ESD Caution.................................................................................. 8 Pin Configuration and Function Descriptions............................. 9 Typical Performance Characteristics ........................................... 11 ...
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AD8108/AD8109—SPECIFICATIONS V = ± +25° kΩ, unless otherwise noted Table 1. Parameter Conditions DYNAMIC PERFORMANCE −3 dB Bandwidth 200 mV p- p-p, R Propagation Delay 2 V p-p, ...
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AD8108/AD8109 Parameter INPUT CHARACTERISTICS Input Offset Voltage Input Voltage Range Input Capacitance Input Resistance Input Bias Current SWITCHING CHARACTERISTICS Enable On Time Switching Time Step Switching Transient (Glitch) POWER SUPPLIES Supply Current Supply Voltage Range PSRR OPERATING TEMPERATURE ...
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TIMING CHARACTERISTICS (SERIAL) Table 2. Timing Characteristics Parameter Serial Data Setup Time CLK Pulse Width Serial Data Hold Time CLK Pulse Separation, Serial Mode CLK to UPDATE Delay UPDATE Pulse Width CLK to DATA OUT Valid, Serial Mode Propagation Delay, ...
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AD8108/AD8109 TIMING CHARACTERISTICS (PARALLEL) Table 4. Timing Characteristics Parameter Data Setup Time CLK Pulse Width Data Hold Time CLK Pulse Separation CLK to UPDATE Delay UPDATE Pulse Width Propagation Delay, UPDATE to Switch On or Off CLK, UPDATE Rise and ...
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Table 6. Operation Truth Table UPDATE CE CLK DATA IN DATA OUT Data Data … D3 parallel f A0 … A2 mode X… ...
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AD8108/AD8109 ABSOLUTE MAXIMUM RATINGS Table 7. Parameter Supply Voltage 1 Internal Power Dissipation AD8108/AD8109 80-Lead Plastic LQFP (ST) Input Voltage Output Short-Circuit Duration 2 Storage Temperature Range 1 Specification is for device in free air (T = 25°C): A 80-lead ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS IN00 1 AGND 2 IN01 3 AGND 4 IN02 5 AGND 6 IN03 7 AGND 8 IN04 9 AGND 10 IN05 11 AGND 12 IN06 13 AGND 14 IN07 15 AGND 16 AVEE 17 AVCC ...
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AD8108/AD8109 Table 8. Pin Function Descriptions Pin No. Mnemonic 11, 13, 15 INxx 57 DATA IN 58 CLK 59 DATA OUT 56 UPDATE 61 RESET SER/PAR 41, 38, 35, 32, 29, 26, ...
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TYPICAL PERFORMANCE CHARACTERISTICS 150Ω FLATNESS 1 0 GAIN –1 2V p-p –2 –3 100k 1M 10M FREQUENCY (Hz) Figure 7. AD8108 Frequency Response – 1kΩ L –20 –30 –40 –50 ALL ...
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AD8108/AD8109 p-p 2 FLATNESS 1 0 GAIN –1 –2 2V p-p –3 100k 1M 10M FREQUENCY (Hz) Figure 13. AD8109 Frequency Response – 1kΩ L –30 –40 –50 –60 –70 ADJACENT –80 –90 –100 ...
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R = 150Ω L –40 –50 –60 –70 –80 –90 10k 100k 1M FREQUENCY (Hz) Figure 19. AD8108 PSRR vs. Frequency 100 56.3 31.6 17.8 10 5.63 3.16 10 100 1k 10k 100k FREQUENCY (Hz) Figure 20. AD8108 Voltage ...
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AD8108/AD8109 – 150Ω L –40 –50 –60 –70 –80 –90 10k 100k FREQUENCY (Hz) Figure 25. AD8109 PSRR vs. Frequency 100.0 56.3 31.6 17.8 10.0 5.63 3.16 10 100 1k 10k FREQUENCY (Hz) Figure 26. AD8109 Voltage Noise ...
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FREQUENCY (Hz) Figure 31. AD8108 Input Impedance vs. Frequency V = 200mV 150Ω –2 –4 –6 –8 30k 100k 1M 10M 100M ...
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AD8108/AD8109 1M 100k 10k 1k 100 100k 1M 10M 30k FREQUENCY (Hz) Figure 37. AD8109 Input Impedance vs. Frequency V = 100mV 150 Ω –2 –4 –6 –8 30k 100k 1M ...
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I/O SCHEMATICS V CC ESD INPUT ESD AVEE Figure 43. Analog Input V CC ESD OUTPUT 1kΩ ESD (AD8109 ONLY) AVEE Figure 44. Analog Output V CC ESD 20kΩ ESD DGND Figure 45. Reset Input ESD INPUT ESD Figure 46. ...
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AD8108/AD8109 THEORY OF OPERATION The AD8108 ( and AD8109 ( share a common core architecture consisting of an array of 64 transconductance (gm) input stages organized as eight 8:1 multiplexers with a common 8-line analog input ...
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AD8108/AD8109. When taken low, the RESET signal will only set each output to the disabled state. This is helpful during power-up to ensure that two parallel outputs will not be active at the same time. After initial power-up, the internal ...
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AD8108/AD8109 CREATING LARGER CROSSPOINT ARRAYS The AD8108/AD8109 are high density building blocks for creating crosspoint arrays of dimensions larger than 8 × 8. Various features, such as output disable, chip enable, and gain-of-1 and-2 options, are useful for creating larger ...
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Using additional crosspoint devices in the design can lower the number of outputs that must be wire-OR’ together. Figure 51 shows a block diagram of a system using eight AD8108s and two AD8109s to create a nonblocking, gain-of-2, ...
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AD8108/AD8109 CROSSTALK Many systems, such as broadcast video, that handle numerous analog signal channels have strict requirements for keeping the various signals from influencing any of the others in the system. Crosstalk is the term used to describe the coupling ...
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If a larger crosspoint array of multiple AD8108/AD8109s is constructed, the numbers grow larger still. Obviously, some subset of all these cases must be selected to be used as a guide for a practical measure ...
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AD8108/AD8109 PCB LAYOUT Extreme care must be exercised to minimize additional crosstalk generated by the system circuit board(s). The areas that must be carefully detailed are grounding, shielding, signal routing, and supply bypassing. The packaging of the AD8108/AD8109 is designed ...
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Figure 53. Component Side Silkscreen Figure 54. Board Layout (Component Side) Rev Page AD8108/AD8109 ...
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AD8108/AD8109 Figure 55. Board Layout (Signal Layer) Figure 56. Board Layout (Power Plane) Rev Page ...
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Figure 57. Board Layout (Bottom Layer) Rev Page AD8108/AD8109 ...
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AD8108/AD8109 EVALUATION BOARD A 4-layer evaluation board for the AD8108/AD8109 is available. The exact same board and external components are used for each device. The only difference is the device itself, which offers a selection of a gain of unity ...
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DVCC DGND NC AVEE AGND AVCC NC P1-1 P1-2 P1-3 P1-4 P1-5 P1-6 P1 CR1 CR2 1N4148 + 0.1µF 10µF 0.1µF 10µF 0.1µF 10µF 1 INPUT 00 INPUT 00 2 AGND 75Ω 3 INPUT 01 INPUT 01 4 ...
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... VIEW A ROTATED 90° CCW 1 ORDERING GUIDE Model Temperature Range AD8108AST −40°C to +85°C 2 AD8108ASTZ −40°C to +85°C AD8109AST −40°C to +85°C 2 AD8109ASTZ −40°C to +85°C AD8108-EB AD8109-EB 1 Details of the lead finish composition can be found on the ADI website Pb-free part ...
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NOTES Rev Page AD8108/AD8109 ...
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AD8108/AD8109 NOTES © 2005 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C01068–0–9/05(B) Rev Page ...