ad7866aru-reel Analog Devices, Inc., ad7866aru-reel Datasheet
ad7866aru-reel
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ad7866aru-reel Summary of contents
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... SUCCESSIVE T/H MUX DRIVERS APPROXIMATION ADC CONTROL LOGIC 12-BIT SUCCESSIVE T/H MUX DRIVERS APPROXIMATION ADC BUF D B AGND AGND DGND CAP © 2003 Analog Devices, Inc. All rights reserved. AD7866 OUTPUT D A OUT A0 RANGE SCLK CS V DRIVE OUTPUT D B OUT www.analog.com ...
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AD7866–SPECIFICATIONS Parameter DYNAMIC PERFORMANCE Signal to Noise + Distortion (SINAD) 2 Total Harmonic Distortion (THD) Peak Harmonic or Spurious Noise (SFDR) 2 Intermodulation Distortion (IMD) Second Order Terms Third Order Terms Channel-to-Channel Isolation SAMPLE AND HOLD 3 Aperture Delay 3 ...
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Parameter CONVERSION RATE Conversion Time 3 Track/Hold Acquisition Time Throughput Rate POWER REQUIREMENTS DRIVE Normal Mode (Static) Operational MSPS S Partial Power-Down Mode Partial Power-Down Mode Full Power-Down Mode 7 Power ...
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AD7866 1 TIMING SPECIFICATIONS Limit at Parameter Unit MIN MAX kHz min SCLK 20 MHz max max CONVERT SCLK 800 ns max max QUIET ...
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... AGND . . . . . . . . . . . . . . . . . . –0 REF Digital Output Voltage to DGND . . . –0 Input Current to Any Pin Except Supplies Operating Temperature Range Commercial (A, B Versions – +125 C Model Temperature Range AD7866ARU –40°C to +125°C AD7866BRU –40°C to +125°C 1 EVAL-AD7866CB 2 EVAL-CONTROL BRD2 ...
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AD7866 Pin No. Mnemonic Function 1 REF SELECT Internal/External Reference Selection. Logic input. If this pin is tied to GND, the on-chip 2.5 V reference is used as the reference source for both ADC A and ADC B. In addition, ...
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Pin No. Mnemonic Function 11 RANGE Analog Input Range and Output Coding Selection. Logic input. The polarity on this pin will determine what input range the analog input channels on the AD7866 will have, and will also select the type ...
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AD7866 TERMINOLOGY Integral Nonlinearity This is the maximum deviation from a straight line passing through the endpoints of the ADC transfer function. The endpoints of the transfer function are zero scale, a point 1 LSB below the first code transition, ...
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PERFORMANCE CURVES TPC 1 shows a typical FFT plot for the AD7866 at 1 MHz sample rate and 300 kHz input frequency. TPC 2 shows the signal-to-(noise + distortion) ratio performance versus input frequency for various supply voltages while sampling ...
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AD7866 0 100mV p-p SINE WAVE –10 2.5V EXT REFERENCE ON V REF –20 –30 –40 –50 – 2.7V DD –70 – 3.6V DD –90 –100 1k 10k ...
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CIRCUIT INFORMATION The AD7866 is a fast, micropower, dual 12-bit, single supply, A/D converter that operates from a 2 5.25 V supply. When operated from either supply supply, the AD7866 is ...
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AD7866 Analog Input Ranges The analog input range for the AD7866 can be selected with either straight binary or twos complement REF REF output coding. The RANGE pin is used to ...
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CS SCLK RANGE D A OUT D B OUT Figure 7. Selecting V CS SCLK RANGE D A OUT D B OUT Figure 8. Selecting Figure 9. ...
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AD7866 Digital Inputs The digital inputs applied to the AD7866 are not limited by the maximum ratings that limit the analog inputs. Instead, the digital inputs applied can and are not restricted by the V 0.3 ...
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EXT REF 100nF REF CAP 2.5V BUF A REF BUF CAP EXT REF Figure 15. Reference Circuit If the on-chip 2.5 V reference is being used, and applied externally to the ...
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AD7866 terminated, and D A and D B will go back into three- OUT OUT state brought high before the second SCLK falling edge, the part will remain in normal mode and will not power down. This ...
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Then, to place the AD7866 in normal mode, a dummy cycle (1 µ µs approximately) should be initiated. If the first valid conversion is performed directly after the dummy conversion, care must be taken to ensure that adequate ...
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AD7866 POWER VS. THROUGHPUT RATE When the AD7866 is in partial power-down mode and not converting, the average power consumption of the ADC decreases at lower throughput rates. Figure 21 shows that as the through- put rate is reduced, the ...
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Bit Bit Name Comment 15 ZERO Leading Zero. This bit will always be a zero output. 14 RANGE The polarity of this bit reflects the analog input range that has been selected with the RANGE pin ...
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AD7866 For example, if the ADSP-2189 had a 20 MHz crystal such that it had a master clock frequency of 40 MHz, then the master cycle time would be 25 ns. If the SCLKDIV register is loaded with the value ...
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Both AGND pins of the AD7866 should be sunk in the AGND plane. Digital and analog ground planes should be joined at only one place. If ...
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AD7866 0.15 0.05 COPLANARITY OUTLINE DIMENSIONS 20-Lead Thin Shrink Small Outline Package [TSSOP] (RU-20) Dimensions shown in millimeters 6.60 6.50 6. 4.50 4.40 4.30 6.40 BSC 1 10 PIN 1 0.65 1.20 BSC MAX 0.20 0.09 0.30 SEATING ...
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Revision History Location 2/03—Data Sheet changed from REV REV. A. Addition to FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . ...
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