AD7790BRMZ Analog Devices Inc, AD7790BRMZ Datasheet
AD7790BRMZ
Specifications of AD7790BRMZ
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AD7790BRMZ Summary of contents
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FEATURES Power Supply: 2 5.25 V operation Normal: 75 µA maximum Power-down: 1 µA maximum RMS noise: 1.1 µV at 9.5 Hz update rate 16-bit p-p resolution Integral nonlinearity: 3.5 ppm typical Simultaneous 50 Hz and 60 Hz ...
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AD7790 TABLE OF CONTENTS AD7790—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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AD7790—SPECIFICATIONS Table 2 5.25 V; REFIN(+) = 2.5 V; REFIN(–) = GND; CDIV1 = CDIV0 = 0; GND = all specifications unless otherwise noted.) MIN MAX Parameter ADC ...
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AD7790 SPECIFICATIONS (continued) Parameter REFERENCE INPUT (continued) 2 Normal Mode Rejection @ 50 Hz Common Mode Rejection @ Hz LOGIC INPUTS All Inputs Except SCLK 2 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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AD7790 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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AD7790 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS SCLK AD7790 AIN(+) 3 TOP VIEW 8 (Not to Scale) AIN(– REF(+) 5 6 03538-0-005 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 for a 16.6 Hz Update Rate 3.0 2.5 2.0 1.5 1.0 0.5 ...
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AD7790 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 = 0x88) 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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AD7790 Bit Location Bit Name Description MR2 0 This bit must be programmed with a Logic 0 for correct operation. MR1 BUF Configures the ADC for buffered or unbuffered mode of operation. If cleared, the ADC operates in unbuffered mode, ...
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ADC CIRCUIT INFORMATION OVERVIEW The AD7790 is a low power ADC that incorporates a ∑-∆ modulator, a buffer, a PGA, and on-chip digital filtering intend- ed for the measurement of wide dynamic range, low frequency signals such as those in ...
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AD7790 DIGITAL INTERFACE As previously outlined, the AD7790’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 ...
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Single Conversion Mode In single conversion mode, the AD7790 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 AD7790 powers up, ...
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AD7790 Continuous Read Mode Rather than write to the communications register each time a conversion is complete to access the data, the AD7790 can be placed in continuous read mode. By writing 001111XX to the communications register, the user only ...
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CIRCUIT DESCRIPTION ANALOG INPUT CHANNEL The AD7790 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 in ...
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AD7790 REFIN(+) without introducing gain errors in the system. Deriv- ing the reference input voltage across an external resistor will mean that the reference input sees a significant external source impedance. External decoupling on the REFIN pins would not be ...
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OUTLINE DIMENSIONS ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although this product features proprietary ESD protection circuitry, permanent damage may occur ...
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AD7790 NOTES © 2003 Analog Devices, Inc. All rights reserved. Trademarks and regis- tered trademarks are the property of their respective companies. C03538-0-8/03(0) Rev Page ...