AD7891BS-1 Analog Devices Inc, AD7891BS-1 Datasheet
AD7891BS-1
Specifications of AD7891BS-1
Related parts for AD7891BS-1
AD7891BS-1 Summary of contents
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FEATURES Fast 12-Bit ADC with 1.6 s Conversion Time 8 Single-Ended Analog Input Channels Overvoltage Protection on Each Channel Selection of Input Ranges for AD7891 +2 2.5 V ...
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AD7891–SPECIFICATIONS Parameter 2 DYNAMIC PERFORMANCE 4 Signal-to-(Noise + Distortion) Ratio @ 25∞ MIN MAX 4 Total Harmonic Distortion 4 Peak Harmonic or Spurious Noise 4 Intermodulation Distortion Second-Order Terms Third-Order Terms 4 Channel-to-Channel Isolation DC ACCURACY Resolution ...
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Parameter A Version LOGIC OUTPUTS Output High Voltage, V 4.0 OH Output Low Voltage, V 0.4 OL DB11to DB0 ± 10 Floating-State Leakage Current 5 Floating-State Capacitance 15 Output Coding Straight (Natural) Binary CONVERSION RATE Conversion Time 1.6 Track/Hold Acquisition ...
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AD7891 TIMING CHARACTERISTICS Parameter Versions t 1.6 CONV Parallel Interface ...
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... Model Input Range AD7891ACHIPS-1 AD7891ACHIPS-2 ± ± AD7891AS-1 ± ± AD7891ASZ-1 ± ± AD7891AP-1 ± ± AD7891AP-1REEL ± ± AD7891BS-1 ± ± AD7891BP-1 ± ± AD7891BP-1REEL ± ± AD7891YS-1 ± ± AD7891YS-1REEL ± ± AD7891YP-1 ± ± AD7891YP-1REEL +2.5 V, ± 2.5 V AD7891AS +2.5 V, ± ...
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AD7891 PLCC MQFP Pin No. Pin No. Mnemonic 1–5 28– INXA INXB 34– AGND 20 14 DGND STANDBY REF OUT/REF ...
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PLCC Pin No. MQFP Pin No. Mnemonic Data I/O Lines There are 12 data input/output lines on the AD7891. When the part is configured for parallel ...
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AD7891 SERIAL INTERFACE MODE FUNCTIONS When the part is configured for serial mode (MODE = 0), five of the 12 data input/output lines provide serial interface functions. These functions are outlined below. PLCC Pin No. MQFP Pin No. Mnemonic 18 ...
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TERMINOLOGY Signal-to-(Noise + Distortion) Ratio This is the measured ratio of signal to (noise + distortion) at the output of the ADC. The signal is the rms amplitude of the fundamental. Noise is the rms sum of all nonfundamental signals ...
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AD7891 CONVERTER DETAILS The AD7891 is an 8-channel, high speed, 12-bit data acquisi- tion system. It provides the user with signal scaling, multiplexer, track/hold, reference, ADC, and high speed parallel and serial interface logic functions on a single chip. The ...
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Serial Interface Mode The serial interface mode is selected by tying the MODE input to a logic low. In this case, five of the data/control inputs of the parallel mode assume serial interface functions. The serial interface on the AD7891 ...
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AD7891 CIRCUIT DESCRIPTION Reference The AD7891 contains a single reference pin labeled REF OUT/ REF IN that either provides access to the part’s own 2.5 V internal reference or to which an external 2.5 V reference can be connected to ...
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Table I. Ideal Code Transition Table for the AD7891-1, Analog Input Input Voltage 2 3 +FSR /2 – 3/2 LSB (9.99268 V, 4.99634 V or 2.49817 V) +FSR/2 – 5/2 LSB (9.98779 V, 4.99390 V or 2.49695 V) +FSR/2 – ...
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AD7891 Track/Hold Amplifier The track/hold amplifier on the AD7891 allows the ADC to accurately convert an input sine wave of full-scale amplitude to 12-bit accuracy. The input bandwidth of the track/hold is greater than the Nyquist rate of the ADC ...
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As in the 8X51 circuit in Figure 7, the way the 68HC11 is informed that a conversion is completed is not shown in the diagram. The EOC line can be used to inform the 68HC11 that a conversion is complete ...
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AD7891 PARALLEL INTERFACING The parallel port on the AD7891 allows the device to be interfaced to microprocessors or DSP processors as a memory mapped or I/O mapped device. The CS and RD inputs are common to all memory peripheral interfacing. ...
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AD7891 to DSP5600x Figure 15 shows a parallel interface between the AD7891 and the DSP5600x series of DSPs. The AD7891 should be mapped into the top 64 locations of Y data memory. If extra wait states are needed in this ...
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AD7891 AD7891 PERFORMANCE Linearity The linearity of the AD7891 is primarily determined by the on-chip 12-bit DAC. This is a segmented DAC that is laser trimmed for 12-bit integral linearity and differential linearity. Typical INL for the AD7891 is ± ...
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Effective Number of Bits The formula for signal-to-(noise + distortion) ratio (see Terminology section) is related to the resolution or number of bits of the converter. Rewriting the formula gives a measure of performance expressed in effective number of bits ...
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AD7891 2.10 2.00 1.95 0.25 MIN VIEW A ROTATED 90 CCW Revision History Location 4/04—Data Sheet changed from REV REV. D. Changes to SPECIFICATIONS . . . . . . . . . . . . . . ...