AD7793BRUZ-REEL Analog Devices Inc, AD7793BRUZ-REEL Datasheet
AD7793BRUZ-REEL
Specifications of AD7793BRUZ-REEL
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AD7793BRUZ-REEL Summary of contents
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FEATURES bits effective resolution RMS noise 4. 16.7 Hz Current: 400 μA typical Power-down: 1 μA maximum Low noise programmable gain instrumentation amp Band gap reference with 4 ppm/°C drift ...
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AD7792/AD7793 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Characteristics..................................................................... 6 Timing Diagrams.......................................................................... 7 Absolute Maximum Ratings............................................................ 8 ESD Caution.................................................................................. 8 Pin Configuration and ...
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SPECIFICATIONS 5.25 V; GND = 0 V; all specifications Table 1. Parameter ADC CHANNEL Output Update Rate 2 No Missing Codes Resolution Output Noise and ...
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AD7792/AD7793 Parameter REFERENCE Internal Reference Internal Reference Initial Accuracy 2 Internal Reference Drift Power Supply Rejection External Reference External REFIN Voltage 2 Reference Voltage Range 2 Absolute REFIN Voltage Limits Average Reference Input Current Average Reference Input Current Drift Normal ...
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Parameter SCLK, CLK, and DIN (Schmitt- Triggered Input (+) T V (– (+) − V (− (+) T V (– (+) − V (− Input Currents Input Capacitance LOGIC ...
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AD7792/AD7793 TIMING CHARACTERISTICS 5.25 V, GND = 0 V, Input Logic Input Logic Table Parameter Limit ...
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TIMING DIAGRAMS DOUT/RDY ( MSB SCLK ( NOTES INPUT OUTPUT Figure 3. Read Cycle Timing Diagram CS ( SCLK ( ...
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AD7792/AD7793 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter AV to GND GND DD Analog Input Voltage to GND Reference Input Voltage to GND Digital Input Voltage to GND Digital Output Voltage ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 4. Pin Function Descriptions Pin No. Mnemonic Description 1 SCLK Serial Clock Input. This serial clock input is for data transfers to and from the ADC. The SCLK has a Schmitt- triggered input, making ...
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AD7792/AD7793 Pin No. Mnemonic Description 15 DOUT/RDY Serial Data Output/Data Ready Output. DOUT/RDY serves a dual purpose. It functions as a serial data output pin to access the output shift register of the ADC. The output shift register can contain ...
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OUTPUT NOISE AND RESOLUTION SPECIFICATIONS EXTERNAL REFERENCE Table 5 shows the output rms noise of the AD7792/AD7793 for some of the update rates and gain settings. The numbers given are for the bipolar input range with an external 2.5 V ...
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AD7792/AD7793 INTERNAL REFERENCE Table 8 shows the output rms noise of the AD7792/AD7793 for some of the update rates and gain settings. The numbers given are for the bipolar input range with the internal 1.17 V reference. These numbers are ...
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TYPICAL PERFORMANCE CHARACTERISTICS 8388800 8388750 8388700 8388650 8388600 8388550 8388500 8388450 0 200 400 READING NUMBER Figure 6. Typical Noise Plot (Internal Reference, Gain = 64, Update Rate = 16.7 Hz) for AD7793 ...
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AD7792/AD7793 ON-CHIP REGISTERS The ADC is controlled and configured via a number of on-chip registers, which are described on the following pages. In the following descriptions, set implies a Logic 1 state and cleared implies a Logic 0 state, unless ...
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STATUS REGISTER RS2, RS1, RS0 = Power-On/Reset = 0x80 (AD7792)/0x88 (AD7793) The status register is an 8-bit read-only register. To access the ADC status register, the user must write to the communications register, select the next operation ...
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AD7792/AD7793 Table 15. Operating Modes MD2 MD1 MD0 Mode Continuous Conversion Mode (Default). In continuous conversion mode, the ADC continuously performs conversions and places the result in the data register. RDY goes low when a conversion is ...
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FS3 FS2 FS1 FS0 CONFIGURATION REGISTER RS2, RS1, RS0 = 0, 1, ...
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AD7792/AD7793 Bit Location Bit Name Description CON7 REFSEL Reference Select Bit. The reference source for the ADC is selected using this bit. REFSEL 0 1 CON6 to 0 These bits must be programmed with a Logic 0 for correct operation. ...
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Table 18. IO Register Bit Designations Bit Location Bit Name Description IO7 to IO4 0 These bits must be programmed with a Logic 0 for correct operation. IO3 to IO2 IEXCDIR1 to Direction of current sources select bits. IEXCDIR0 IEXCDIR1 ...
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AD7792/AD7793 ADC CIRCUIT INFORMATION OVERVIEW The AD7792/AD7793 are low power ADCs that incorporate a ∑-Δ modulator, a buffer, reference, in-amp, and an on-chip digital filter intended for the measurement of wide dynamic range, low frequency signals such as those in ...
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FREQUENCY (Hz) Figure 16. Filter Response at 470 Hz Update Rate DIGITAL INTERFACE The programmable functions of the AD7792/AD7793 are controlled using a set of on-chip ...
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AD7792/AD7793 Single Conversion Mode In single conversion mode, the AD7792/AD7793 are placed in shutdown mode between conversions. When a single conver- sion is initiated by setting MD2, MD1, MD0 the mode register, the AD7792/AD7793 power ...
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Continuous Read Rather than write to the communications register each time a conversion is complete to access the data, the AD7792/AD7793 can be configured so that the conversions are placed on the DOUT/ RDY line automatically. By writing 01011100 to ...
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AD7792/AD7793 CIRCUIT DESCRIPTION ANALOG INPUT CHANNEL The AD7792/AD7793 have three differential analog input channels. These are connected to the on-chip buffer amplifier when the device is operated in buffered mode and directly to the modulator when the device is operated ...
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BURNOUT CURRENTS The AD7792/AD7793 contain two 100 nA constant current generators, one sourcing current from AV sinking current from AIN(–) to GND. The currents are switched to the selected analog input pair. Both currents are either on or off, depending ...
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AD7792/AD7793 AV MONITOR DD Along with converting external voltages, the ADC can be used to monitor the voltage on the AV pin. When Bit CH2 to DD Bit CH0 equal 1, the voltage on the AV DD attenuated by 6, ...
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The ground planes of the AD7792/AD7793 should be allowed to run under the AD7792/AD7793 to prevent noise coupling. The power supply lines to the AD7792/AD7793 should use as wide a trace as possible to provide low impedance paths and reduce ...
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AD7792/AD7793 APPLICATIONS INFORMATION The AD7792/AD7793 provide a low cost, high resolution analog-to-digital function. Because the analog-to-digital function is provided by a ∑-Δ architecture, the parts are more immune to noisy environments, making them ideal for use in sensor measurement and ...
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TEMPERATURE MEASUREMENT USING AN RTD To optimize a 3-wire RTD configuration, two identically matched current sources are required. The AD7792/AD7793, which contain two well-matched current sources, are ideally suited to these applications. One possible 3-wire configuration is shown in Figure ...
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... AD7792BRUZ 1 –40°C to +105°C 1 AD7792BRUZ-REEL –40°C to +105°C AD7793BRU –40°C to +105°C AD7793BRU-REEL –40°C to +105°C 1 AD7793BRUZ –40°C to +105°C 1 AD7793BRUZ-REEL –40°C to +105°C 1 EVAL-AD7792EBZ 1 EVAL-AD7793EBZ RoHS Compliant Part. 5.10 5.00 4. 4.50 6.40 4 ...
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NOTES Rev Page AD7792/AD7793 ...
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AD7792/AD7793 NOTES ©2004–2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D04855-0-3/07(B) Rev Page ...