AD7890ARZ-10 Analog Devices Inc, AD7890ARZ-10 Datasheet
AD7890ARZ-10
Specifications of AD7890ARZ-10
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AD7890ARZ-10 Summary of contents
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FEATURES Fast 12-bit ADC with 5.9 μs conversion time Eight single-ended analog input channels Selection of input ranges: ±10 V for AD7890- 4.096 V for AD7890 2.5 V for AD7890-2 Allows separate access to ...
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AD7890 TABLE OF CONTENTS Features .............................................................................................. 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Product Highlights ........................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Specifications .................................................................. 5 Absolute Maximum Ratings............................................................ 6 ESD Caution.................................................................................. 6 Pin Configuration and ...
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SPECIFICATIONS AGND = DGND = 0 V, REF unless otherwise noted. MAX Table 1. Parameter A Versions DYNAMIC PERFORMANCE 2 Signal to (Noise + Distortion) Ratio 70 2 ...
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AD7890 Parameter A Versions LOGIC INPUTS Input High Voltage, V 2.4 INH Input Low Voltage, V 0.8 INL Input Current, I ± Input Capacitance LOGIC OUTPUTS Output High Voltage, V 4.0 OH Output Low Voltage, ...
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TIMING SPECIFICATIONS ± 5%, AGND = DGND = 0 V, REF Parameter Limit MIN 3 f 100 CLKIN 2.5 t 0.3 × t ...
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AD7890 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Parameter V to AGND DGND DD Analog Input Voltage to AGND AD7890-10, AD7890-4 AD7890-2 Reference Input Voltage to AGND Digital Input Voltage to DGND Digital Output ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 2. Pin Function Descriptions Pin No. Mnemonic Description 1 AGND Analog Ground. Ground reference for track/hold, comparator, and DAC. 2 SMODE Control Input. Determines whether the part operates in its external clocking (slave) or ...
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AD7890 Pin No. Mnemonic Description 14 SHA IN Track/Hold Input. The input to the on-chip track/hold is applied to this pin high impedance input and the input voltage range 2 AGND ...
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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 A/D converter. The signal is the rms amplitude of the fundamental. Noise is the rms sum of ...
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AD7890 CONTROL REGISTER The control register for the AD7890 contains 5 bits of information. Six serial clock pulses must be provided to the part in order to write data to the control register (seven if the write is required to ...
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THEORY OF OPERATION CONVERTER DETAILS The AD7890 is an 8-channel, 12-bit, single supply, serial data acquisition system. It provides the user with signal scaling, multiplexer, track/hold, reference, ADC, and versatile serial logic functions on a single chip. The signal scaling ...
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AD7890 Table 4. Ideal Input/Output Code Table for the AD7890-10 1 Analog Input Digital Output Code Transition 2 +FSR/2 − 1 LSB (9.995117 V) 011 . . . 110 to 011 . . . 111 +FSR/2 − 2 LSBs (9.990234 ...
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The acquisition time of the track/ hold amplifier begins at this point. REFERENCE The AD7890 contains a single reference pin, labeled REF OUT/ REF IN, which either provides access to the part’s ...
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AD7890 When using the device in the external-clocking mode, the output register can be read at any time and the most up-to-date conversion result is obtained. However, reading data from the output register or writing data to the control register ...
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In the self-clocking mode, the AD7890 indicates when conversion is complete by bringing the RFS line low and initiating a serial data transfer. In the external clocking mode, there is no indication of when conversion is complete. In many applications, ...
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AD7890 C FUNCTIONING EXT The C input on the AD7890 provides a means of determining EXT how long after a new channel address is written to the part that a conversion can take place. The reason behind this is two-fold. ...
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SERIAL INTERFACE The AD7890’s serial communications port provides a flexible arrangement to allow easy interfacing to industry-standard microprocessors, microcontrollers, and digital signal processors. A serial read to the AD7890 accesses data from the output register via the DATA OUT line. ...
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AD7890 Write Operation Figure 11 shows a write operation to the control register of the AD7890. The TFS input is taken low to indicate to the part that a serial write is about to occur. TFS going low initiates the ...
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SIMPLIFYING THE INTERFACE To minimize the number of interconnect lines to the AD7890, the user can connect the RFS and TFS lines of the AD7890 together and read and write from the part simultaneously. In this case, new control register ...
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AD7890 MICROPROCESSOR/MICROCONTROLLER INTERFACE The AD7890’s flexible serial interface allows for easy connection to the serial ports of DSP processors and microcontrollers. Figure 14 through Figure 17 show the AD7890 interfaced to a number of different microcontrollers and DSP processors. In ...
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The serial clock rate from the 68HC11 is limited to significantly less than the allowable input serial clock frequency with which the AD7890 can operate result, the time to read data from the part is actually longer than ...
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AD7890 In the scheme outlined here, the user does not have to worry about monitoring the end of conversion. Once conversion is complete, the AD7890 takes care of transmitting back its conversion result to the processor. Once the 16 bits ...
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PERFORMANCE LINEARITY The linearity of the AD7890 is primarily determined by the on- chip 12-bit D/A converter. This is a segmented DAC that is laser trimmed for 12-bit integral linearity and differential linearity. Typical relative numbers for the part are ...
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AD7890 8000 SAMPLING FREQUENCY = 102.4kHz 7000 T = 25°C A 6000 5000 4000 3000 2000 1000 0 (X–4) (X–3) (X–2) (X–1) X (X+1) (X+2) (X+3) (X+4) CODE Figure 21. Histogram of 8192 Conversions with Write During Conversion DYNAMIC PERFORMANCE ...
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OUTLINE DIMENSIONS 24 1 0.210 (5.33) MAX 0.150 (3.81) 0.130 (3.30) 0.115 (2.92) 0.022 (0.56) 0.018 (0.46) 0.014 (0.36) CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS (IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR REFERENCE ONLY AND ARE NOT APPROPRIATE FOR ...
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AD7890 0.30 (0.0118) 0.10 (0.0039) COPLANARITY 0.10 15.60 (0.6142) 15.20 (0.5984 7.60 (0.2992) 7.40 (0.2913) 1 10.65 (0.4193) 12 10.00 (0.3937) 2.65 (0.1043) 2.35 (0.0925) SEATING 0.51 (0.0201) 1.27 (0.0500) 0.33 (0.0130) PLANE BSC 0.31 (0.0122) 0.20 (0.0079) ...
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... AD7890BNZ-10 −40°C to +85°C AD7890AR-10 −40°C to +85°C AD7890AR-10REEL −40°C to +85°C 1 AD7890ARZ-10 −40°C to +85°C 1 AD7890ARZ-10REEL −40°C to +85°C AD7890BR-10 −40°C to +85°C AD7890BR-10REEL −40°C to +85°C AD7890BRZ-10 1 −40°C to +85°C 1 AD7890BRZ-10REEL − ...
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AD7890 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C01357-0-9/06(C) Rev Page ...