AD7789BRMZ Analog Devices Inc, AD7789BRMZ Datasheet
AD7789BRMZ
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AD7789BRMZ Summary of contents
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FEATURES AD7788: 16-bit resolution AD7789: 24-bit resolution Power Supply: 2 5.25 V operation Normal: 75 μA maximum Power-down: 1 μA maximum RMS noise: 1.5 μV AD7788: 16-bit p-p resolution AD7789: 19-bit p-p resolution (21.5 bits effective) Integral nonlinearity: ...
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AD7788/AD7789 TABLE OF CONTENTS Features .............................................................................................. 1 Interface ............................................................................................. 1 Applications....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 AD7789 .......................................................................................... 3 AD7788 .......................................................................................... 4 AD7788/AD7789.......................................................................... 5 Timing Characteristics ................................................................ 6 Timing ...
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SPECIFICATIONS AD7789 5.25 V; REFIN(+) = 2.5 V; REFIN(−) = GND; GND = 0 V; all specifications T DD Table 1. 1 Parameter ADC CHANNEL SPECIFICATION Output Update Rate ADC CHANNEL 2 No Missing Codes ...
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AD7788/AD7789 AD7788 grade 2 5. grade); REFIN(+) = 2.5 V; REFIN(−) = GND; GND = 0 V; all specifications unless ...
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AD7788/AD7789 Table 3. Parameter LOGIC INPUTS 1 All Inputs Except SCLK V , Input Low Voltage INL V , Input High Voltage INH SCLK Only (Schmitt-Triggered Input) V (+) − (+) ...
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AD7788/AD7789 TIMING CHARACTERISTICS 5.25 V (AD7788B and AD7789 Input Logic Input Logic Table Parameter Limit MIN MAX t ...
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TIMING DIAGRAMS DOUT/RDY (O) I (1.6mA WITH V SINK 100µA WITH OUTPUT 1.6V PIN 50pF I (200µA WITH V SOURCE 100µA WITH V DD Figure 2. Load Circuit for Timing Characterization CS ( MSB t ...
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AD7788/AD7789 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 5. 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 ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 6. Pin Function Descriptions Pin No. Mnemonic Description 1 SCLK Serial Clock Input for Data Transfers to and from the ADC. The SCLK has a Schmitt-triggered input, making the interface suitable for opto-isolated applications. ...
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AD7788/AD7789 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 ...
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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 otherwise ...
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AD7788/AD7789 Table 8. Register Selection RS1 RS0 Register 0 0 Communications register during a write operation 0 0 Status register during a read operation 0 1 Mode register 1 0 Reserved 1 1 Data register Table 9. Channel Selection CH1 ...
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MODE REGISTER (RS1, RS0 = 0, 1; Power-On/Reset = 0x02) The mode register is an 8-bit register from which data can be read from or written to. This register is used to configure the ADC for range, to set unipolar ...
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AD7788/AD7789 ADC CIRCUIT INFORMATION The AD7788/AD7789 are low power ADCs that incorporate a Σ-Δ modulator and on-chip digital filtering intended for the measurement of wide dynamic range, low frequency signals, such as those in pressure transducers, weigh scales, and temper- ...
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The serial interface can be reset by writing a series the DIN input Logic 1 is written to the AD7788/AD7789 for at least 32 serial clock cycles, the serial interface is reset. This ensures that ...
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AD7788/AD7789 Continuous Read Mode Rather than write to the communications register each time a conversion is complete to access the data, the AD7788/AD7789 can be placed in continuous read mode. By writing 001111XX to the communications register, the user needs ...
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CIRCUIT DESCRIPTION ANALOG INPUT CHANNEL The AD7788/AD7789 have one differential analog input channel that is connected to the modulator, thus, the input is unbuffered. Note that this unbuffered input path provides a dynamic load to the driving source. Therefore, resistor/capacitor ...
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AD7788/AD7789 Reference voltage sources like those recommended in the pre- vious section (for example, ADR391) 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 ...
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... AD7788ARM-REEL −40°C to +85°C 1 AD7788ARMZ −40°C to +85°C AD7789BRM −40°C to +105°C AD7789BRM-REEL −40°C to +105°C 1 AD7789BRMZ −40°C to +105°C 1 AD7789BRMZ-REEL −40°C to +105°C EVAL-AD7788EB EVAL-AD7789EB Pb-free part. 3.10 3.00 2. 5.15 3.10 4.90 3 ...
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AD7788/AD7789 NOTES ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. C03539-0-3/06(B) Rev Page ...