AD8112-EVALZ Analog Devices Inc, AD8112-EVALZ Datasheet
AD8112-EVALZ
Specifications of AD8112-EVALZ
AD8112-EVALZ Summary of contents
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... L The AD8112 includes eight independent output buffers that can be placed into a disabled state for paralleling crosspoint outputs so that off channel loading is minimized. The AD8112 has a gain of +2. It operates on voltage supplies of ± ±12 V while consuming only current, respectively. The channel switching is performed via a serial digital control (which ...
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... AD8112 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Characteristics (Serial) .................................................. 5 Timing Characteristics (Parallel) ............................................... 6 Absolute Maximum Ratings............................................................ 7 ESD Caution.................................................................................. 7 Power Dissipation......................................................................... 7 Pin Configuration and Function Descriptions............................. 9 I/O Schematics............................................................................ 11 Typical Performance Characteristics ........................................... 12 Theory of Operation ...................................................................... 17 REVISION HISTORY 2/07—Revision 0: Initial Version Calculation of Power Dissipation ...
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... AD8112 Unit MHz MHz MHz MHz MHz ns ns V/μs V/μs % Degrees % nV/√Hz nV/√ ppm/°C Ω kΩ μ ...
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... AD8112 Parameter SWITCHING CHARACTERISTICS Enable On Time Switching Time Step Switching Transient (Glitch) POWER SUPPLIES Supply Current DYNAMIC PERFORMANCE Supply Voltage Range PSRR OPERATING TEMPERATURE RANGE Temperature Range θ JA Conditions 50% update to 1% settling AV outputs enabled, no load ± outputs disabled ± outputs enabled, no load ± ...
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... IH 20 μA max 2.7 V min 0.5 V max Rev Page Limit Min Typ Max 20 1 100 100 200 100 200 OUT00 (D0 TRANSFER DATA FROM SERIAL REGISTER TO PARALLEL LATCHES DURING LOW LEVEL −400 μA min −400 μA max AD8112 Unit μ 3.0 mA min ...
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... AD8112 TIMING CHARACTERISTICS (PARALLEL) Table 4. 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 Fall Times RESET Time 1 CLK LATCHED UPDATE 0 = TRANSPARENT Table 5 ...
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... ESD CAUTION POWER DISSIPATION The AD8112 is operated with ± ±12 V supplies and can Rating drive loads down to 150 Ω (± 600 Ω (±12 V), resulting 26 large range of possible power dissipations. For this reason, ...
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... AD8112 Table 7. Operation Truth Table CE UPDATE CLK DATA IN DATA OUT Data Data ... D4, N ... A2 Parallel Mode PARALLEL D1 DATA D2 D3 (OUTPUT D4 ENABLE) SER/PAR DATA (SERIAL) CLK CLK CLK CE UPDATE OUT00 EN OUT01 EN OUT02 EN OUT03 EN A0 OUT04 EN OUT05 EN A1 OUT06 EN A2 OUT07 OUT00 OUT00 B0 B1 ...
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... Analog Outputs for Channel Numbers 00 Through 07. OUT00 to 1 OUT07 AGND Analog Ground for Inputs and Switch Matrix. Must be connected for Digital Circuitry. CC DGND Ground for Digital Circuitry. AV −5 V for Inputs and Switch Matrix. EE Rev Page AD8112 DGND 74 AGND 73 IN07 72 71 AGND IN06 70 69 ...
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... AD8112 Pin No. 21, 22, 26, 30, 34, 38 50, 46, 42 52, 48, 44 23, 25, 27, 29, 31, 33, 35, 37 Chanel numbers 00 through 15 for analog inputs channel numbers 00 through 07 for analog outputs. Mnemonic Description for Inputs and Switch Matrix for Output Amplifier. This pin is shared by Channel Numbers xx and yy. ...
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... Figure 7. Analog Input V CC ESD ESD AV EE Figure 8. Analog Output V CC ESD 20kΩ RESET ESD DGND Figure 9. Reset Input OUTPUT Rev Page AD8112 V CC ESD INPUT ESD DGND Figure 10. Logic Input V CC 2kΩ ESD OUTPUT ESD DGND Figure 11. Logic Output ...
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... AD8112 TYPICAL PERFORMANCE CHARACTERISTICS 3 0 –3 –6 0.01 0.1 1 FREQUENCY (MHz) Figure 12. Small-Signal Bandwidth ± 0.3 0.2 0.1 0 –0.1 –0.2 –0.3 0.1 1 FREQUENCY (MHz) Figure 13. Small-Signal Gain Flatness ± –3 –6 0.1 1 FREQUENCY (MHz) Figure 14. Large-Signal Bandwidth ± 100 = 150 Ω 200 mV p-p Figure 15 ...
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... ALL HOSTILE –50 –60 ADJACENT –70 –80 –90 0.01 0 FREQUENCY (MHz) = ± 600 Ω –70 –75 –80 –85 SECOND HARMONIC –90 –95 THIRD HARMONIC 0.001 0.01 0.1 FREQUENCY (MHz) = ± 600 Ω AD8112 p-p OUT 100 = 20 V p-p OUT p-p OUT ...
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... AD8112 300 250 200 V = ±12V 150 600Ω L 100 SERIES RESISTANCE (Ω) Figure 24. Capacitive Load vs. Series Resistance for Less than 30% Overshoot 10k 1k 100 FREQUENCY (MHz) Figure 25. Disabled Output Impedance vs. Frequency 100 10 1 0.1 0 FREQUENCY (MHz) Figure 26. Enabled Output Impedance vs. Frequency ± ...
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... Figure 35. Small-Signal Pulse Response Rev Page +PSRR –PSRR 0.01 0.1 1 FREQUENCY (MHz) Figure 33. PSRR vs. Frequency ± ±12V 600Ω p-p OUT V = ± 150Ω OUT 0 FREQUENCY (MHz) Figure 34. Off Isolation vs. Frequency 100ns/DIV = ± AD8112 p-p 100 = 600 Ω L ...
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... AD8112 500mV/DIV 100ns/DIV Figure 36. Large-Signal Pulse Response, V UPDATE 2V/DIV V OUT INPUT 0 100ns/DIV Figure 37. Switching Time ± UPDATE 1V/DIV OUTPUT 20mV/DIV 100ns/DIV Figure 38. Switching Transient ± 5V/DIV = ± 150 Ω Figure 39. Large-Signal Pulse Response 2V/DIV INPUT 1 10V/DIV = 150 Ω L 1V/DIV 20mV/DIV = 150 Ω ...
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... THEORY OF OPERATION The AD8112 has a gain of +2 and is a crosspoint array with eight outputs, each of which can be connected to any one of 16 inputs. Organized by output row, 16 switchable transconductance stages are connected to each output buffer in the form of a 16-to-1 multiplexer. Each of the 16 rows of transconductance stages are wired in parallel to the 16 input pins, for a total array of 256 trans- conductance stages ...
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... AD8112 When calculating on-chip power dissipation necessary to include the rms current being delivered to the load multiplied by the rms voltage drop on the AD8112 output devices. The dissipation of the on-chip, 4 kΩ feedback resistor network must also be included. For a sinusoidal output, the on-chip ...
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... One important consideration when using parallel programming is that the RESET signal does not reset all registers in the AD8112. When taken low, the RESET signal only sets 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 ...
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... CREATING UNITY-GAIN CHANNELS The channels in the AD8112 each have a gain of +2. This gain is necessary, as opposed to a gain of unity, to restrict the voltage on internal nodes to less than the breakdown voltage desired to create channels with an overall gain of unity, a resistive divider can be used at the input to divide the signals by 2 ...
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... Video signals usually use 75 Ω transmission lines that need to be terminated with this value of resistance at each end. When such a source is delivered to one of the AD8112 inputs, the high input impedance does not properly terminate these signals. Therefore, the line should be terminated with a 75 Ω shunt resistor to ground ...
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... R TERM IN64 TO IN79 1kΩ TERM IN80 TO IN95 1kΩ TERM IN96 TO IN111 1kΩ TERM IN112 TO IN127 1kΩ TERM RANK 1 (8 × AD8112) 128:16 1kΩ 4 AD8112 1kΩ 4 1kΩ 4 AD8112 1kΩ 4 1kΩ 4 AD8112 1kΩ 4 16:8 NONBLOCKING (16:16 BLOCKING) 1kΩ AD8112 1kΩ ...
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... When there are many signals in close proximity in a system, as undoubtedly is the case in a system that uses the AD8112, the crosstalk issues can be quite complex. A good understanding of the nature of crosstalk and some definition of terms is required in order to specify a system that uses one or more AD8112s ...
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... Areas of Crosstalk A practical AD8112 circuit must be mounted to some sort of circuit board to connect it to power supplies and measurement equipment. Great care has been taken to create a characteriza- tion board (also available as an evaluation board) that adds minimum crosstalk to the intrinsic device ...
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... On the output side, the crosstalk can be reduced by driving a lighter load. Although the AD8112 is specified with excellent differential gain and phase when driving a standard 150 Ω video load, the crosstalk is higher than the minimum obtainable crosstalk due to the high output currents ...
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... The areas that must be carefully designed are grounding, shielding, signal routing, and supply bypassing. The packaging of the AD8112 is designed to help minimize crosstalk. Each input is separated from each other input by an analog ground pin. All of these AGNDs should be directly connected to the ground plane of the circuit board ...
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... C = OPTIONAL SMOOTHING CAPACITOR CONNECT 0.01µF 0.01µF 0.01µ 21 AD8112 Figure 48. Evaluation Board Schematic Rev Page AD8112 OUTPUT 00 0.01µF 75Ω 53 OUT00 00/01 OUTPUT 01 0.01µF 75Ω 51 OUT01 01/02 OUTPUT 02 0.01µF 75Ω 49 OUT02 02/03 OUTPUT 02 0.01µF 75Ω 47 OUT03 ...
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... PLANE VIEW A ROTATED 90° CCW ORDERING GUIDE Model Temperature Range AD8112JSTZ 1 0°C to 70°C 1 AD8112-EVALZ Pb-free part. ©2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. 1.60 MAX 0.75 100 1 0.60 0.45 PIN 1 0 ...