AD7732BRU Analog Devices Inc, AD7732BRU Datasheet
AD7732BRU
Specifications of AD7732BRU
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AD7732BRU Summary of contents
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FEATURES High resolution ADC 24 bits no missing codes ±0.0015% nonlinearity Optimized for fast channel switching 18-bit p-p resolution (21 bits effective) at 500 Hz 16-bit p-p resolution (19 bits effective kHz 14-bit p-p resolution (18 bits effective) ...
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AD7732 TABLE OF CONTENTS AD7732—Specifications.................................................................. 3 Timing Specifications....................................................................... 6 Absolute Maximum Ratings............................................................ 8 Typical Performance Characteristics ............................................. 9 Output Noise and Resolution Specification................................ 10 Chopping Enabled...................................................................... 10 Chopping Disabled..................................................................... 11 Pin Configurations and Functional Descriptions ...................... 12 Register Description....................................................................... 14 ...
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AD7732—SPECIFICATIONS Table 1. (–40°C to +105° ± 5 REFIN(–) = AGND; RA, RB, RC, RD open circuit; AIN Range = ± Parameter ADC PERFORMANCE CHOPPING ENABLED Conversion Time Rate ...
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AD7732 Parameter 1, 9 BIAS Pin Impedance 1, 9 RA, RB, RC, RD Pin Impedance Input Resistor Matching Input Resistor Temp. Coefficient REFERENCE INPUTS 1, 10 REFIN(+) to REFIN(–) Voltage NOREF Trigger Voltage REFIN(+), REFIN(–) 1 Common-Mode Voltage 11 Reference ...
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Parameter 14 DV Current (Normal Mode Power Dissipation (Normal Mode +DV Current (Standby Mode Power Dissipation (Standby Mode) 1 Specifications are not production tested but guaranteed by design and/or characterization data at initial ...
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AD7732 TIMING SPECIFICATIONS Table 2. ( ± ± 5%; Input Logic Logic noted.) Parameter Min Master ...
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SCLK DOUT MSB Figure 2. Read Cycle Timing Diagram SCLK DIN MSB Figure 3. Write Cycle Timing Diagram ...
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AD7732 ABSOLUTE MAXIMUM RATINGS Table 25°C, unless otherwise noted. A Parameter AV to AGND DGND DD DD AGND to DGND AIN to AGND RA, RB, RC AGND BIAS ...
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TYPICAL PERFORMANCE CHARACTERISTICS 25 24 CHOP = FILTER WORD Figure 5. No Missing Codes Performance, Chopping Enabled 25 24 CHOP = ...
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AD7732 OUTPUT NOISE AND RESOLUTION SPECIFICATION The AD7732 can be operated with chopping enabled or disabled, allowing the ADC to be programmed to either optimize the throughput rate and channel switching time or to optimize the offset drift performance. Noise ...
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Chopping Disabled The second mode, in which the AD7732 is configured with chopping disabled (CHOP = 0), provides faster conversion time while still maintaining high resolution. Table 7 to Table 9 show the –3 dB frequencies and typical performance versus ...
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AD7732 PIN CONFIGURATIONS AND FUNCTIONAL DESCRIPTIONS SCLK MCLKIN MCLKOUT RESET AD7732 TOP VIEW (Not to Scale) SYNC/ ...
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Pin No. Mnemonic 8 SYNC/ BIAS1(+) 12 AIN1(+) 13 AIN0(+) 14 BIAS0(+) 15 BIAS0(–) 16 AIN0(–) 17 AIN1(–) 18 BIAS1(– REFIN(+) 22 REFIN(–) 23 AGND 24 RDY 25 DOUT 26 ...
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AD7732 REGISTER DESCRIPTION Table 11. Register Summary Register Addr (hex) Communications 00 I/O Port 01 Revision 02 Test 03 ADC Status 04 Checksum 05 ADC Zero-Scale Calibration 06 ADC Full-Scale 07 1 Channel Data 08, 0A Channel Zero-Scale Cal. 1 ...
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Register Access The AD7732 is configurable through a series of registers. Some of them configure and control general AD7732 features, while others are specific to each channel. The register data widths vary from 8 bits to 24 bits. All registers ...
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AD7732 I/O Port Register 8 Bits, Read/Write Register, Address 01h, Default Value 30h + Digital Input Value × 40h The bits in this register are used to configure and access the digital I/O port on the AD7732. Bit Bit 7 ...
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ADC Status Register 8 Bits, Read-Only Register, Address 04h, Default Value 00h In conversion modes, the register bits reflect the individual channel status. When a conversion is complete, the corresponding channel data register is updated and the corresponding RDY bit ...
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AD7732 Channel Zero-Scale Calibration Registers 24 Bits, Read/Write Registers, Address 10h, 12h, Default Value 800000h These registers hold the particular channel zero-scale calibration coefficients. The value in these registers is used in conjunction with the value in the corresponding channel ...
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Channel Setup Registers 8 Bits, Read/Write Register, Address 28h, 2Ah, Default Value 00h These registers are used to configure the selected channel, to configure its input voltage range, and to set up the corresponding channel status register. Bit Bit 7 ...
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AD7732 Mode Register 8 Bits, Read/Write Register, Address 38h, 3Ah, Default Value 00h The mode register configures the part and determines its operating mode. Writing to the mode register clears the ADC status register, sets the RDY pin to a ...
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MD2 MD1 MD0 Operating Mode Idle Mode The default mode after power-on or reset. The AD7732 automatically returns to this mode after any calibration or after a single conversion Continuous Conversion Mode The AD7732 ...
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AD7732 DIGITAL INTERFACE DESCRIPTION Hardware The AD7732 serial interface can be connected to the host device via the serial interface in several different ways. The CS pin can be used to select the AD7732 as one of several circuits connected ...
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Reset The AD7732 can be reset by the RESET pin or by writing a reset sequence to the AD7732 serial interface. The reset sequence is N × × 1, which could be the data sequence 00h + ...
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AD7732 Dump Mode When the DUMP bit in the mode register is set to 1, the channel status register will be read immediately by a read of the channel data register, regardless of whether the status or the data register ...
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START CONTINUOUS CONVERSION SERIAL INTERFACE RDY CH0 CONVERSION START CONTINUOUS CONVERSION SERIAL INTERFACE RDY CH0 CONVERSION CS SCLK DIN 38h 48h DOUT RDY WRITE WRITE COMM. MODE COMM. REGISTER REGISTER REGISTER Continuous Read (Continuous Conversion) Mode When the Cont RD ...
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AD7732 CIRCUIT DESCRIPTION The AD7732 is a sigma-delta ADC that is intended for the measurement of wide dynamic range, low frequency signals in industrial process control, instrumentation, and PLC systems. It contains thin film resistor dividers, a multiplexer, an input ...
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Analog Input’s Extended Voltage Range The AD7732 output data code span corresponds to the nominal input voltage range. The ADC is functional outside the nominal input voltage range, but the performance might degrade. The sigma-delta modulator was designed to fully ...
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AD7732 Multiplexer, Conversion, and Data Output Timing The specified conversion time includes one or two settling and sampling periods and a scaling time. With chopping enabled (Figure 25), a conversion cycle starts with a settling time of 43 MCLK cycles ...
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Frequency Response The sigma-delta modulator runs at ½ the MCLK frequency, which is effectively the sampling frequency. Therefore, the Nyquist frequency is ¼ the MCLK frequency. The digital filter, in association with the modulator, features the frequency response of a ...
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AD7732 I/O Port The AD7732 P0 pin can be used as a general-purpose digital I/O pin. The P1 pin ( SYNC /P1) can be used as a general- purpose digital I/O pin or to synchronize the AD7732 with other devices ...
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ANALOG INPUTS ±11.5V COMMON- MODE VOLTAGE ±10V DIFFERENTIAL (MAX ±16.5V VOLTAGE ABSOLUTE VOLTAGE TO AGND) ±10V DIFFERENTIAL VOLTAGE AV DD +VIN VOUT AD780 TEMP + 10 µ F 0.01 µ F High Common-Mode Voltage Application Using additional thin film resistors ...
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... Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality. Table 18. Ordering Guide AD7732 Products Temperature Package AD7732BRU –40°C to +105°C © 2003 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective companies. Printed in the U.S.A. ...