ad7790brm-reel Analog Devices, Inc., ad7790brm-reel Datasheet
ad7790brm-reel
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ad7790brm-reel Summary of contents
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... When operating from supply, the power dissipation for the part is 225 µW maximum housed in a 10-lead MSOP. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 Fax: 781.326.8703 © 2003 Analog Devices, Inc. All rights reserved. AD7790 INTERNAL CLOCK SERIAL ...
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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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... ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality. Table 17. Ordering Guide Model Temperature Range AD7790BRM –40°C to +105°C AD7790BRM-REEL –40°C to +105°C 3.00 BSC 10 6 4.90 BSC 3.00 BSC 1 ...
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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 ...