AD7899 Analog Devices, AD7899 Datasheet
AD7899
Specifications of AD7899
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AD7899 Summary of contents
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... The part is offered in three versions with different analog input ranges. The AD7899-1 offers the standard industrial ranges of ± and ± the AD7899-2 offers a unipolar range 2 and the AD7899-3 has an input range of ± 2.5 V. AD7899 V DRIVE 2 ...
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... Relative Accuracy (INL) 3 Differential Nonlinearity (DNL) AD7899-1 Input Voltage Range Input Current 3 Positive Gain Error 3 Negative Gain Error Bipolar Zero Error AD7899-2 Input Voltage Range Input Current 3 Positive Gain Error 3 Offset Error AD7899-3 Input Voltage Range Input Current 3 Positive Gain Error ...
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... Input Capacitance LOGIC OUTPUTS Output High Voltage Output Low Voltage DB13–DB0 High Impedance Leakage Current 4 Capacitance Output Coding AD7899-1, AD7899-3 AD7899-2 CONVERSION RATE Conversion Time 2, 3 Track/Hold Acquisition Time Throughput Time POWER REQUIREMENTS Normal Mode ...
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... AD7899 TIMING CHARACTERISTICS to T and valid for and 5 V MAX DRIVE A, B and S Parameter Versions t 2.2 CONV 2.46 t 0.3 ACQ t 120 EOC 180 5 t – External V 2 WAKE-UP REF Read Operation ...
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... Analog Input Voltage to AGND AD7899-1 (± Range ± AD7899-1 (± Range – +18 V AD7899 – +18 V AD7899 – +18 V Reference Input Voltage to AGND . . . –0 Digital Input Voltage to DGND . . . . . –0 Digital Output Voltage to DGND . . . . –0 Operating Temperature Range Commercial (A, B Version – ...
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... Conversion Clock Input. CLKIN is an externally applied clock which allows the user to control the conversion rate of the AD7899. If the CLKIN input is high on the rising edge of CONVST an externally applied clock will be used as the conversion clock. If the CLKIN is low on the rising edge of CONVST the internal laser-trimmed oscillator is used as the conversion clock ...
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... ± 10 V), 2 × – 3/2 LSB (AD7899 2.5 V range) after the Uni- REF , polar Offset Error has been adjusted out. Unipolar Offset Error (AD7899-2) This is the deviation of the first code transition ( ...
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... ± input voltage range, the AD7899-2 where the input can be configured for 2.5 V input voltage range and the AD7899-3 which handles input voltage range ± 2.5 V. The amount of current flowing into the analog input will depend on the analog input range and the analog input voltage ...
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... LSB +FSR – 7/2 LSB GND + 5/2 LSB GND + 3/2 LSB GND + 1/2 LSB NOTES 1 FSR is Full-Scale Range and 2.5 V and for AD7899-2 with LSB = FSR/16384 and is 0.153 2.5 V) and 0.305 for AD7899-2 with V REF AD7899 ...
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... V INA TRACK/HOLD V INB For the AD7899- kΩ and kΩ. The resistor input stage is followed by the high input impedance stage of the track/hold amplifier. The designed code transitions take place midway between suc- cessive integer LSB values (i.e., 1/2 LSB, 3/2 LSBs, 5/2 LSBs etc.) LSB size is given by the formula, 1 LSB = FSR/16384. ...
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... As each conversion com- pletes the BUSY/EOC pin will pulse low for one clock period (EOC function) indicating that the conversion result is available. Figure 8 shows the timing and control sequence of the AD7899 in Continuous Conversion Mode. Reading Data from the AD7899 Data is read from the part via a 14-bit parallel data bus with standard CS and RD signals ...
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... For example, with a throughput rate of 10 kSPS and an external reference, the AD7899 will be powered up for 4.2 µs out of every 100 µs (2 µs for wake-up time and 2.2 µs for conversion time). Therefore, the average power consumption drops × 4.2% or approxi- mately 3 ...
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... The AD7899 is tested using two input frequencies. In this case the second and third order terms are of different significance. The second order terms are usually distanced in frequency from the original sine waves while the third order terms are usually at a frequency close to the input frequencies ...
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... This maps the AD7899 into external data memory. The RD signal from the TMS320 is used to enable the ADC data onto the data bus. The AD7899 has a fast parallel bus so there are no wait state requirements. The following instruction is used to read the conversion results from ...
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... PIN 1 0.0118 (0.30) 0.0040 (0.10) 0.078 (1.98) 0.068 (1.73) 0.008 (0.203) 0.002 (0.050) AD7899–Revision History Location Data Sheet changed from REV REV. A. Edit to Timing page heading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Edit to Converter Details section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Edit to Figure OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 28-Lead Small Outline (R-28) 0.7125 (18.10) ...
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