AD7896 Analog Devices, AD7896 Datasheet
AD7896
Specifications of AD7896
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AD7896 Summary of contents
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... This offers consider- able space saving over alternative solutions. 2. Low Power, Single-Supply Operation. The AD7896 operates from a single 2 5.5 V supply and consumes only 9 mW typical. The automatic power- down mode, where the part goes into power down once conversion is complete and “ ...
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... AD7896–SPECIFICATIONS Parameter 2 DYNAMIC PERFORMANCE Signal-to-(Noise + Distortion) Ratio @ 25° MIN MAX 3 Total Harmonic Distortion (THD) 3 Peak Harmonic or Spurious Noise 3 Intermodulation Distortion (IMD) Second Order Terms Third Order Terms DC ACCURACY Resolution Minimum Resolution for Which No Missing Codes Are Guaranteed 3 Relative Accuracy ...
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... µA max 2 3 µA max = 5 V ± 10 µA max = 5 V ± 10% 500 V DD µW max 13 2 ± 10 and timed from a voltage level of 1 and the setup time required for the user’s 4 AD7896 ...
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... ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD7896 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality ...
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... SCLK Serial Clock Input. An external serial clock is applied to this input to obtain serial data from the AD7896. A new serial data bit is clocked out on the falling edge of this serial clock. Data is guaranteed valid for 10 ns after this falling edge so data can be accepted on the falling edge when a fast serial clock is used. ...
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... The theoretical signal-to-(noise + distortion) ratio for an ideal N-bit converter with a sine wave input is given by: Signal-to-(Noise + Distortion) = (6.02N + 1.76) dB Thus, for a 12-bit converter, this is 74 dB. Total Harmonic Distortion Total harmonic distortion (THD) is the ratio of the rms sum of harmonics to the fundamental. For the AD7896 defined as THD ...
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... The conversion clock for the part is generated inter- nally using a laser-trimmed clock oscillator circuit. Conversion time for the AD7896 is 8 µs in the high sampling mode (14 µs for the auto sleep mode), and the track-and-hold acquisition time is 1.5 µs. To obtain optimum performance from the part, the read operation should not occur during the conversion or during 400 ns prior to the next conversion ...
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... CONVST, and new data from this conversion is available in the output register of the AD7896. A read operation accesses this data. This read operation consists of 16 clock cycles, and the length of this read operation depends on the serial clock frequency. For the fastest throughput rate (with a serial clock of 10 MHz opera- tion), the read operation will take 1.6 µ ...
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... The serial clock input does not need to be continuous during the serial read operation. The 16 bits of data (four leading zeros and 12-bit conversion result) can be read from the AD7896 in a number of bytes. However, the SCLK input must remain low between the two bytes. ...
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... AD7896. A simple AND function on this port bit and the serial clock from the 8X51/L51 will provide this function. The port bit should be high to select the AD7896 and low when it is not selected ...
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... AD7896. The histogram plot for 8192 conversions of the same dc input now shows a larger spread of codes with the rms noise for the AD7896 increasing to 279 µV. This effect will vary depending on where the serial clock edges appear with respect to the bit trials of the conversion process ...
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... AD7896 from /2. The sampling frequency SAMPLING is 102.4 kHz. The plot shows that the AD7896 converts an input sine wave of 51.2 kHz to an effective numbers of bits of 11.25, which equates to a signal-to-(noise + distortion) level of 69 dB. 12.00 11 ...
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... SEATING 0.10 0.17 (0.0067) PLANE COMPLIANT TO JEDEC STANDARDS MS-012AA CONTROLLING DIMENSIONS ARE IN MILLIMETERS; INCH DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF MILLIMETER EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN –13– AD7896 (Q-8) Dimensions shown in inches and (millimeters) 0.005 (0.13) 0.055 (1.40) MIN MAX 8 5 0.310 (7.87) PIN 1 0 ...
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... AD7896 Revision History Location 7/03—Data Sheet changed from REV REV. C. Changes to SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Changes to Figure Edits to ORDERING GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Added ESD Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Updated OUTLINE DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 –14– Page REV. C ...
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