AD7791BRM Analog Devices Inc, AD7791BRM Datasheet
AD7791BRM
Specifications of AD7791BRM
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AD7791BRM Summary of contents
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FEATURES Power Supply: 2 5.25 V operation Normal: 75 µA max Power-down: 1 µA max RMS noise: 1.1 µV at 9.5 Hz update rate 19.5-bit p-p resolution (22 bits effective resolution) Integral nonlinearity: 3.5 ppm typical Simultaneous 50 ...
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AD7791 TABLE OF CONTENTS AD7791—Specifications.................................................................. 3 Timing Characteristics..................................................................... 5 Absolute Maximum Ratings............................................................ 7 Pin Configuration and Function Descriptions............................. 8 Typical Performance Characteristics ............................................. 9 On-Chip Registers .......................................................................... 10 Communications Register (RS1, RS0 = 0, 0) ......................................................................... 10 Status Register (RS1, ...
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AD7791—SPECIFICATIONS Table 2 5.25 V; REFIN(+) = 2.5 V; REFIN(–) = GND; GND = 0 V; CDIV1 = CDIV0 = 0; DD all specifications unless otherwise noted.) MIN MAX Parameter ADC ...
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AD7791 SPECIFICATIONS (continued) Parameter REFERENCE INPUT (continued) 2 Normal Mode Rejection @ 50 Hz Common Mode Rejection @ Hz LOGIC INPUTS 2 All Inputs Except SCLK V ...
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TIMING CHARACTERISTICS Table 2 5.25 V; GND = 0 V, REFIN(+) = 2.5 V, REFIN(–) = GND, CDIV1 = CDIV0 = 0, Input Logic Input Logic ...
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AD7791 DOUT/RDY (O) I (1.6mA WITH V SINK 100µA WITH V TO OUTPUT 1.6V PIN 50pF I (200µA WITH V SOURCE 100µA WITH V Figure 2. Load Circuit for Timing Characterization CS ( MSB ...
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ABSOLUTE MAXIMUM RATINGS Table 25°C, unless otherwise noted.) A Parameter V to GND DD Analog Input Voltage to GND Reference Input Voltage to GND Total AIN/REFIN Current (Indefinite) Digital Input Voltage to GND Digital Output Voltage to ...
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AD7791 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS SCLK AD7791 AIN(+) 3 TOP VIEW 8 (Not to Scale) AIN(– REF(+) 5 6 04227-0-005 Figure 5. Pin Configuration Table 4. Pin Function Descriptions Pin No. Mnemonic ...
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TYPICAL PERFORMANCE CHARACTERISTICS 0 –10 –20 –30 –40 –50 –60 –70 –80 –90 –100 –110 –120 100 FREQUENCY (Hz) Figure 6. Frequency Response with 16.6 Hz Update Rate 100 V = ...
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AD7791 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 (RS1, RS0 = 0, 0; POWER-ON/RESET = 0x8C) 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 read, ...
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AD7791 Bit Location Bit Name Description MR3 BO Burnout Current Enable Bit. When this bit is set the user, the 100 nA current sources in the signal path are enabled. When the burnout currents ...
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Table 12. Update Rates FS2 FS1 FS0 120 100 9.5 ...
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AD7791 ADC CIRCUIT INFORMATION OVERVIEW The AD7791 is a low power ADC that incorporates a ∑-∆ modulator, a buffer and on-chip digital filtering intended for the measurement of wide dynamic range, low frequency signals such as those in pressure transducers, ...
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DIGITAL INTERFACE As previously outlined, the AD7791’s programmable functions are controlled using a set of on-chip registers. Data is written to these registers via the part’s serial interface and read access to the on-chip registers is also provided by this ...
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AD7791 Single Conversion Mode In single conversion mode, the AD7791 is placed in shutdown mode between conversions. When a single conversion is initi- ated by setting MD1 to 1 and MD0 the mode register, the AD7791 powers ...
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Continuous Read Mode Rather than write to the communications register each time a conversion is complete to access the data, the AD7791 can be placed in continuous read mode. By writing 001111XX to the communications register, the user needs only ...
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AD7791 CIRCUIT DESCRIPTION ANALOG INPUT CHANNEL The AD7791 has one differential analog input channel. This is 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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Reference voltage sources like those recommended above (e.g., ADR391) will typically have low output impedances and are, therefore, tolerant to having decoupling capacitors on REFIN(+) without introducing gain errors in the system. Deriving the reference input voltage across an external ...
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... Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality. Table 16. Ordering Guide Model Temperature Range AD7791BRM –40°C to +105°C AD7791BRM-REEL –40°C to +105°C © 2003 Analog Devices, Inc. All rights reserved. Trademarks and regis- tered trademarks are the property of their respective companies. 3.00 BSC ...