AD7862 Analog Devices, AD7862 Datasheet
AD7862
Specifications of AD7862
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AD7862 Summary of contents
Page 1
... A2 sampled and converted simultaneously thus preserving the relative phase information of the signals on both analog inputs. The part accepts an analog input range (AD7862-10), 2.5 V (AD7862-3) and 0–2.5 V (AD7862-2). Overvoltage protection on the analog inputs for the part allows the input voltage respectively, without causing damage ...
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... Bipolar Zero Error Bipolar Zero Error Match AD7862-2 Unipolar Offset Error Unipolar Offset Error Match ANALOG INPUTS AD7862-10 Input Voltage Range Input Resistance AD7862-3 Input Voltage Range Input Resistance AD7862-2 Input Voltage Range Input Current REFERENCE INPUT/OUTPUT REF IN Input Voltage Range 4 ...
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... DGND . . . . . . . . . . . . . . . . . . . . . . . . . –0 AGND to DGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . Analog Input Voltage to AGND AD7862- AD7862 AD7862 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 – +85 C Extended (S Version – +125 C Storage Temperature Range . . . . . . . . . . . . – ...
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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 AD7862 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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... Input Number 2 of Channel B. Analog Input voltage ranges of B2 (AD7862-3) and 0 V–2.5 V (AD7862-2 Input Number 2 of Channel A. Analog Input voltage ranges (AD7862-10), 2 (AD7862-3) and 0 V–2.5 V (AD7862-2). 19 VREF Reference Input/Output. This pin is connected to the internal reference through a series resistor and is the output reference source for the analog-to-digital converter ...
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... Positive Full-Scale Error This is the deviation of the last code transition ( 110 111) from the ideal 4 VREF – 3/2 LSB (AD7862- range) or VREF – 3/2 LSB (AD7862-3, 2.5 V range after the Bipolar Offset Error has been adjusted out Positive Full-Scale Error (AD7862- ...
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... C and a maximum error over temperature of 25 mV. If the application requires a reference with a tighter tolerance or the AD7862 needs to be used with a system reference, the user has the option of connecting an external reference to this VREF pin. The external reference will effectively overdrive the internal while the second read reference and provide the reference source for the ADC ...
Page 8
... AD7862 currents, as the resistor stage is followed by a high input impedance stage of the track/hold amplifier. For the AD7862-10 7 and For the AD7862- 6.5 k and R3 is open circuit. For the AD7862-10 and AD7862-3, the designed code transi- tions occur on successive integer LSB values (i.e., 1 LSB, 2 LSBs, 3 LSBs ...
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... CONVST, and new data from this conversion is available in the output latch of the AD7862. A read operation accesses this data. If the multiplexer select A0 is low, the first and second read pulses after the first conversion access the result from Channel A (V – ...
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... Mode 1 operation. DYNAMIC SPECIFICATIONS The AD7862 is specified and 100% tested for dynamic perfor- mance specifications as well as traditional dc specifications such as Integral and Differential Nonlinearity. These ac specifications are required for the signal processing applications such as phased array sonar, adaptive filters and spectrum analysis. These applica- tions require information on the ADC’ ...
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... Figure 7 shows a histogram plot for 8192 conversions input using the AD7862 with 5 V supply. The analog input was set at the center of a code transition. It can be seen that all the codes appear in the one output bin indicating very good noise performance from the ADC. ...
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... Figure 12. This shows very good integral linearity performance from the AD7862 at an input frequency of 10 kHz. The absence of large spikes in the plot shows good differential linearity. Sim- plified versions of the formulas used are outlined below. ...
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... TMS32010 or from an external source, and the TMS32010 is interrupted when both conversions have been completed. The following instruction is used to read the conver- sion results from the AD7862: IN D,ADC where D is Data Memory address, and ADC is the AD7862 address. REV. 0 TMS32010 Figure 15. AD7862–TMS32010 Interface OPTIONAL AD7862– ...
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... The MC68000 AS and R/W outputs are used to generate a separate RD input signal for the AD7862 used to drive the 68000 DTACK input to allow the processor to execute a normal read operation to the AD7862. The conversion results are read using the following 68000 instruction: MOVE ...
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... A common read signal from the microprocessor drives the RD input of all AD7862s. Each AD7862 is designated a unique address selected by the address decoder. The reference output REV AD7862 number 1 is used to drive the reference input of all other AD7862s in the circuit shown in Figure 20. One VREF I C pin can drive several AD7862 REF IN pins ...
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... AD7862 28-Pin Plastic DIP (N-28) 1.565 (39.70) 1.380 (35.10 0.580 (14.73) 0.485 (12.32 PIN 1 0.060 (1.52) 0.250 0.015 (0.38) (6.35) MAX 0.150 (3.81) MIN 0.200 (5.05) 0.022 (0.558) 0.100 0.070 SEATING 0.125 (3.18) (1.77) (2.54) PLANE 0.014 (0.356) BSC MAX 28-Pin Cerdip (Q-28) 0.005 (0.13) MIN 0.100 (2.54) MAX 28 15 0.610 (15.49) 0.500 (12.70 PIN 1 0.015 1 ...