AD7863 Analog Devices, AD7863 Datasheet
AD7863
Specifications of AD7863
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AD7863 Summary of contents
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... The part accepts an analog input range of ±10 V (AD7863-10), ±2.5 V (AD7863-3), and 2.5 V (AD7863-2). Overvoltage protection on the analog inputs for the part allows the input voltage ±17 V, ± respectively, without causing damage ...
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... Peak Harmonic or Spurious Noise........................................... 15 DC Linearity Plot ....................................................................... 15 Power Considerations................................................................ 16 Microprocessor Interfacing........................................................... 17 AD7863 to ADSP-2100 Interface ............................................. 17 AD7863 to ADSP-2101/ADSP-2102 Interface ....................... 17 AD7863 to TMS32010 Interface .............................................. 17 AD7863 to TMS320C25 Interface............................................ 17 AD7863 to MC68000 Interface ................................................ 18 AD7863 to 80C196 Interface .................................................... 18 Vector Motor Control ................................................................ 18 Multiple AD7863s ...................................................................... 19 Applications Hints.......................................................................... 20 PC Board Layout Considerations............................................. 20 Ground Planes ............................................................................ 20 Power Planes ............................................................................... 20 Supply Decoupling ...
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... Channel-to-Channel Isolation DC ACCURACY Resolution Minimum Resolution for Which No Missing Codes are Guaranteed 4 Relative Accuracy 4 Differential Nonlinearity AD7863-10, AD7863-3 4 Positive Gain Error 4 Positive Gain Error Match Negative Gain Error 4 4 Negative Gain Error Match Bipolar Zero Error Bipolar Zero Error Match ...
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... For best dynamic performance of the AD7863, ATE device testing has to be performed with power supply decoupling in place. In the AD7863 power-down mode of operation, the leakage current associated with these decoupling capacitors is greater than that of the AD7863 supply current. Therefore, the 40 nA typical figure shown is characterized and guaranteed by design figure, which reflects the supply current of the AD7863 without decoupling in place. The maximum figure shown in the Conditions/Comments column reflects the AD7863 with supply decoupling in place— ...
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... Test Conditions/Comments Conversion time Acquisition time setup time hold time CONVST pulse width RD pulse width Data access time after falling edge of RD Bus relinquish time after rising edge of RD Time between consecutive reads Quiet time AD7863 ...
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... Parameter V to AGND DGND DD Analog Input Voltage to AGND AD7863-10 AD7863-3 AD7863-2 Reference Input Voltage to AGND Digital Input Voltage to DGND Digital Output Voltage to DGND Operating Temperature Range Commercial (A Version and B Version) Storage Temperature Range Junction Temperature SOIC Package, Power Dissipation θ ...
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... AGND Analog Ground. Ground reference for mux, track/hold, reference, and DAC circuitry Input Number 2 of Channel B. Analog input voltage ranges of ±10 V (AD7863-10), ±2.5 V (AD7863-3), and 2.5 V (AD7863-2 Input Number 2 of Channel A. Analog input voltage ranges of ±10 V (AD7863-10), ±2.5 V (AD7863-3), and ...
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... N-bit converter with a sine wave input is given by Signal to (Noise + Distortion) = (6.02N + 1.76) dB For a 14-bit converter, this is 86.04 dB. Total Harmonic Distortion Total harmonic distortion (THD) is the ratio of the rms sum of harmonics to the fundamental. For the AD7863 it is defined ...
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... If the application requires a reference with a tighter tolerance or the AD7863 needs to be used with a system reference, the user has the option of connecting an external reference to this V pin. The external reference effectively overdrives the internal reference and thus provides the reference source for the ADC ...
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... For the AD7863-10 kΩ kΩ and kΩ. For the AD7863- kΩ and R3 is open circuit. For the AD7863-10 and AD7863-3, the designed code transitions occur on successive integer LSB values (that is, 1 LSB, 2 LSBs, 3 LSBs ...
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... AD7863. In the sequence shown, a conversion is initiated on the falling edge of CONVST . This places both track-and-holds into hold simultaneously and new data from this conversion is available in the output register of the AD7863 5.2 μs later. The BUSY CONVST t 3 BUSY ...
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... AD7863 Read Options Apart from the read operation previously described and displayed in Figure 7, other CS and RD combinations can result in different channels/inputs being read in different combinations. Suitable combinations are shown in Figure 8, Figure 9, and Figure 10 DATA A1 A2 Figure 8. Read Option A (A0 is Low) ...
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... CONVST and new data from this conversion is available in the output latch of the AD7863. A read operation accesses this data. If the multiplexer select A0 is low, the first and second read pulses after the first conversion accesses the result from Channel A (V respectively) ...
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... SNR data can be obtained. Figure 13 shows a typical 8192 point FFT plot of the AD7863 with an input signal of 10 kHz and a sampling frequency of 175 kHz. The SNR obtained from this graph is −80.72 dB. It should be noted that the harmonics are taken into account when calculating the SNR ...
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... THD specification where it is the ratio of the rms sum of the individual distortion products to the rms amplitude of the fundamental expressed in dBs. In this case, the input consists of two equal amplitude, low distortion sine waves. Figure 15 shows a typical IMD plot for the AD7863. 0 –10 –20 – ...
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... AD7863 POWER CONSIDERATIONS In the automatic power-down mode the part can be operated at a sample rate that is considerably less than 175 kHz. In this case, the power consumption is reduced and depends on the sample rate. Figure 18 shows a graph of the power consumption vs. sampling rates from 100 kHz in the automatic power- down mode. The conditions are 5 V supply at 25° ...
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... ADSP-2100 or from an external source. The AD7863 BUSY line provides an interrupt to the ADSP-2100 when conversion is completed on both channels. The two conversion results can then be read from the AD7863 using two successive reads to the same memory address. The following instruction reads one of the two results: ...
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... MC68000 interrupts, consult the MC68000 users manual. The MC68000 AS and R/ W outputs are used to generate a separate RD input signal for the AD7863 used to drive the MC68000 DTACK input to allow the processor to execute a normal read operation to the AD7863. The conversion results are read using the following MC68000 instruction: MOVE ...
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... The reference output AD7863 Number 1 is used to drive the reference input of all other AD7863s in the circuit shown in Figure 25. One V ISOLATION AMPLIFIERS be used to provide the reference to several other AD7863s. Alternatively, an external or system reference can be used to drive all V scale tracking between all channels ...
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... PC board, and the analog power plane (V provide power to all AD7863 power pins, voltage reference circuitry and any input amplifiers, if needed. A suitable low noise amplifier for the AD7863 is the AD797, one for each input. Ensure that the +V amplifier are individually decoupled to AGND. ...
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... Wide Body (RW-28) Dimensions shown in millimeters and (inches) 10.50 10.20 9. 5.60 5.30 8.20 5.00 7.80 7. 1.85 1.75 1.65 0.38 SEATING 0.22 PLANE 0.65 BSC COMPLIANT TO JEDEC STANDARDS MO-150-AH Figure 28. 28-Lead Shrink Small Outline Package [SSOP] (RS-28) Dimensions shown in millimeters Rev Page 45° 8° 0° 1.27 (0.0500) 0.33 (0.0130) 0.40 (0.0157) 0.20 (0.0079) 0.25 0.09 8° 0.95 4° 0.75 0° 0.55 AD7863 ...
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... AD7863ARS-3 ±2.5 V AD7863ARS-3REEL ±2.5 V AD7863ARS-3REEL7 ±2 AD7863ARSZ-3 ±2 AD7863ARSZ-3REEL ±2 AD7863ARSZ-3REEL7 ±2.5 V AD7863BR-3 ±2.5 V AD7863BR-3REEL ±2.5 V AD7863BR-3REEL7 ±2 AD7863BRZ-3 ±2.5 V AD7863AR 2.5 V AD7863AR-2REEL 2.5 V AD7863AR-2REEL7 2 AD7863ARZ 2 AD7863ARZ-2REEL 2 AD7863ARZ-2REEL7 2.5 V AD7863ARS ...
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... NOTES Rev Page AD7863 ...
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... AD7863 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D06411-0-11/06(B) Rev Page ...