ad7921arm-reel Analog Devices, Inc., ad7921arm-reel Datasheet
ad7921arm-reel
Related parts for ad7921arm-reel
ad7921arm-reel Summary of contents
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... The parts feature a standard successive approximation ADC with accurate control of the sampling instant via a CS input and once-off conversion control. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 Fax: 781.326.8703 © 2004 Analog Devices, Inc. All rights reserved. SCLK CS DOUT DIN , thereby DD ...
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AD7911/AD7921 TABLE OF CONTENTS Specifications..................................................................................... 3 AD7911 Specifications................................................................. 3 AD7921 Specifications................................................................. 5 Timing Specifications .................................................................. 7 Timing Diagrams.......................................................................... 7 Timing Examples.......................................................................... 8 Absolute Maximum Ratings............................................................ 9 ESD Caution.................................................................................. 9 Pin Configurations and Function Descriptions ......................... 10 Terminology .................................................................................... 11 Typical ...
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SPECIFICATIONS AD7911 SPECIFICATIONS Temperature range for A Grade from −40°C to +85° MHz SCLK SAMPLE Table 1. Parameter DYNAMIC PERFORMANCE Signal-to- Noise and Distortion (SINAD) 2 Total Harmonic ...
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AD7911/AD7921 Parameter CONVERSION RATE Conversion Time 2 Track-and-Hold Acquisition Time Throughput Rate POWER REQUIREMENTS Normal Mode (Static) Normal Mode (Operational) Full Power-Down Mode (Static) Full Power-Down Mode (Dynamic) 4 Power Dissipation Normal Mode (Operational) Full Power-Down ...
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AD7921 SPECIFICATIONS Temperature range for A Grade from −40°C to +85° MHz SCLK SAMPLE Table 2. Parameter DYNAMIC PERFORMANCE Signal-to-Noise and Distortion (SINAD) 2 Signal-to-Noise Ratio (SNR) 2 ...
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AD7911/AD7921 Parameter CONVERSION RATE Conversion Time 2 Track-and-Hold Acquisition Time Throughput Rate POWER REQUIREMENTS Normal Mode (Static) Normal Mode (Operational) Full Power-Down Mode (Static) Full Power-Down Mode (Dynamic) 4 Power Dissipation Normal Mode (Operational) Full Power-Down ...
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TIMING SPECIFICATIONS Guaranteed by characterization. All input signals are specified with (10 MIN MAX Table 3. ...
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AD7911/AD7921 TIMING EXAMPLES Figure 6 and Figure 7 show some of the timing parameters from the Timing Specifications section. Timing Example 1 As shown in Figure 7, when MHz and the throughput is SCLK 250 kSPS, the ...
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ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 4. Parameter V to GND DD Analog Input Voltage to GND Digital Input Voltage to GND Digital Output Voltage to GND Input Current to Any Pin except Supplies Operating ...
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AD7911/AD7921 PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS 8-LEAD TSOT DIN 1 8 AD7911/ SCLK 2 7 AD7921 TOP VIEW DOUT (Not to Scale Figure 8. 8-Lead TSOT Pin Configuration Table 5. Pin Function Descriptions TSOT MSOP ...
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TERMINOLOGY Integral Nonlinearity The maximum deviation from a straight line passing through the endpoints of the ADC transfer function. For the AD7911/ AD7921, the endpoints of the transfer function are zero scale, a point 1 LSB below the first code ...
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AD7911/AD7921 Intermodulation Distortion With inputs consisting of sine waves at two frequencies, fa and fb, any active device with nonlinearities creates distortion products at sum and difference frequencies of mfa ± nfb, where ...
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TYPICAL PERFORMANCE CHARACTERISTICS Figure 10 and Figure 11 show typical FFT plots for the AD7921 and AD7911, respectively 250 kSPS sample rate and 100 kHz input frequency. Figure 12 shows the SINAD ratio performance versus the input frequency ...
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AD7911/AD7921 1 2. 250kSPS SAMP TEMPERATURE = 25°C 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 0 512 1024 1536 2048 2560 CODE Figure 14. AD7921 INL Performance 1 2.7V DD ...
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CIRCUIT INFORMATION The AD7911/AD7921 are fast, 2-channel, 10-/12-bit, single supply, analog-to-digital converters (ADCs), respectively. The parts can be operated from a 2. 5.25 V supply. When operated from either supply supply, ...
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AD7911/AD7921 TYPICAL CONNECTION DIAGRAM Figure 22 shows a typical connection diagram for the AD7911/ AD7921 taken internally from V REF should be well decoupled. This provides an analog input range The conversion ...
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Table 7 provides some typical performance data with various op amps used as the input buffer, and a 50 kHz input tone under the same setup conditions. Table 7. AD7921 Performance for Various Input Buffers Op Amp in the Input ...
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AD7911/AD7921 MODES OF OPERATION The two modes of operation of the AD7911/AD7921 are normal mode and power-down mode. The mode of operation is selected by controlling the logic state of the CS signal. The point at which CS is pulled ...
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CS SCLK DIN DOUT THE PART BEGINS TO POWER UP THE PART GOES INTO TRACK SCLK DIN CHANNEL FOR NEXT CONVERSION DOUT INVALID DATA POWER-UP TIME The power-up time of the AD7911/AD7921 is 1 µs, which ...
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AD7911/AD7921 POWER VS. THROUGHPUT RATE By using the power-down mode on the AD7911/AD7921 when not converting, the average power consumption of the ADC decreases at lower throughput rates. Figure 29 shows how, as the throughput rate is reduced, the device ...
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SERIAL INTERFACE Figure 30 and Figure 31 show the detailed timing diagrams for serial interfacing to the AD7921 and AD7911, respectively. The serial clock provides the conversion clock and also controls the transfer of information from the AD7911/AD7921 during conversion. ...
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AD7911/AD7921 MICROPROCESSOR INTERFACING The serial interface on the AD7911/AD7921 allows the parts to be directly connected to a range of microprocessors. This section explains how to interface the AD7911/AD7921 with some of the more common microcontroller and DSP serial interface ...
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For example, the ADSP-2189 has a master clock frequency of 40 MHz. If the SCLKDIV register is loaded with the value of 3, then an SCLK of 5 MHz is obtained, and eight master clock periods elapse for every one ...
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AD7911/AD7921 APPLICATION HINTS GROUNDING AND LAYOUT The printed circuit board that houses the AD7911/AD7921 should be designed such that the analog and digital sections are separated and confined to certain areas of the board. This facilitates the use of ground ...
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... AD7911AUJ-R2 −40°C to +85°C AD7911AUJ-REEL7 −40°C to +85°C AD7921ARM −40°C to +85°C AD7921ARM-REEL −40°C to +85°C AD7921ARM-REEL7 −40°C to +85°C AD7921AUJ-R2 −40°C to +85°C AD7921AUJ-REEL7 −40°C to +85°C 1 Linearity error here refers to integral nonlinearity. ...
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AD7911/AD7921 NOTES Rev Page ...
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NOTES Rev Page AD7911/AD7921 ...
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... AD7911/AD7921 NOTES © 2004 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D04350–0–4/04(0) Rev Page ...