EVAL-AD7796EBZ Analog Devices Inc, EVAL-AD7796EBZ Datasheet
EVAL-AD7796EBZ
Specifications of EVAL-AD7796EBZ
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EVAL-AD7796EBZ Summary of contents
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FEATURES RMS noise Instrumentation amp Temperature sensor Internal clock oscillator Simultaneous 50 Hz/60 Hz rejection Update rate: 4. 123 Hz Current: 250 μA typ Power-down: 1 μA Power supply: 2 5.25 V –40°C to ...
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AD7796/AD7797 TABLE OF CONTENTS Features .............................................................................................. 1 Interface ............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Timing Characteristics..................................................................... 5 Timing Diagrams.......................................................................... 6 Absolute Maximum Ratings............................................................ 7 Thermal Resistance ...................................................................... ...
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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 RMS Noise and ...
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AD7796/AD7797 Parameter INTERNAL/EXTERNAL CLOCK Internal Clock 2 Frequency Duty Cycle External Clock Frequency Duty Cycle LOGIC INPUTS 2 CS Input Low Voltage, V INL Input High Voltage, V INH SCLK, CLK, and 2 DIN (Schmitt-Triggered Input) V (+) T V ...
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TIMING CHARACTERISTICS 5.25 V, GND = 0 V, Input Logic Input Logic Table Parameter Limit at ...
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AD7796/AD7797 TIMING DIAGRAMS DOUT/RDY (O) SCLK ( MSB SCLK ( INPUT OUTPUT Figure 3. Read Cycle Timing Diagram CS ( ...
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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 to ...
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AD7796/AD7797 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 5. 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, ...
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RMS NOISE AND RESOLUTION SPECIFICATIONS Table 6 shows the rms noise of the AD7796/AD7797 for some of the update rates. The numbers given are for the bipolar input range with an external 2.5 V reference. These numbers are typical and ...
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AD7796/AD7797 TYPICAL PERFORMANCE CHARACTERISTICS –20 –40 0 100 200 300 400 500 600 SAMPLES Figure 6. AD7797 Noise ( Update Rate = 16.7 Hz) REF DD 17.5 15.0 12.5 10.0 7.5 5.0 2.5 ...
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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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AD7796/AD7797 STATUS REGISTER RS2, RS1, RS0 = Power-On/Reset = 0x80 The status register is an 8-bit read-only register. To access the ADC status register, the user must write to the communication register, select the next operation to ...
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Table 13. 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 complete. ...
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AD7796/AD7797 CONFIGURATION REGISTER RS2, RS1, RS0 = Power-On/Reset = 0x0710 The configuration register is a 16-bit read/write register. This register is used to configure the ADC for unipolar or bipolar mode, enable or disable the burnout currents, ...
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OFFSET REGISTER RS2, RS1, RS0 = Power-On/Reset = 0x8000 (AD7796)/0x800000 (AD7797) The analog input channel has an offset register that holds the offset calibration coefficient for the channel. This register is 16 bits wide on the AD7796 ...
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AD7796/AD7797 ADC CIRCUIT INFORMATION OVERVIEW The AD7796/AD7797 are low power ADCs that incorporate a Σ-Δ modulator, in-amp, and an on-chip digital filter intended for measuring wide dynamic range, low frequency signals, such as those in pressure transducers and weigh scales. ...
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DIGITAL INTERFACE As outlined in the On-Chip Registers section, the AD7796/ AD7797 programmable functions are controlled by 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 ...
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AD7796/AD7797 Single Conversion Mode In single conversion mode, the AD7796/AD7797 are placed in shutdown mode between conversions. When a single conver- sion is initiated by setting MD2, MD1, and MD0 in the mode register and 1, respectively, ...
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Continuous Read Mode Rather than write to the communication register each time a conversion is complete to access the data, the AD7796/AD7797 can be configured to automatically place the conversions on the DOUT/ RDY line. By writing 01011100 to the ...
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AD7796/AD7797 CIRCUIT DESCRIPTION ANALOG INPUT CHANNEL The AD7796/AD7797 have one differential analog input channel. The input channel feeds into a high impedance input stage of the amplifier. Therefore, the input can tolerate signifi- cant source impedances and is tailored for ...
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RESET The circuitry and serial interface of the AD7796/AD7797 can be reset by writing 32 consecutive 1s to the device. This resets the logic, the digital filter, and the analog modulator, while all on-chip registers are reset to their default ...
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AD7796/AD7797 GROUNDING AND LAYOUT Because the analog input and reference input of the ADC are differential, most of the voltages in the analog modulator are common-mode voltages. The excellent common-mode reject- ion of the part removes common-mode noise on these ...
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APPLICATIONS The AD7796/AD7797 offer a high resolution analog-to-digital function. Because the analog-to-digital function is provided by a Σ-Δ architecture, the parts are more immune to noisy environments, making them ideal for use in sensor measurement, and industrial and process-control applications. ...
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... COMPLIANT TO JEDEC STANDARDS MO-153-AB Figure 18. 16-Lead Thin Shrink Small Outline Package [TSSOP] (RU-16) Dimensions shown in millimeters Package Description 16-Lead TSSOP 16-Lead TSSOP 16-Lead TSSOP 16-Lead TSSOP Evaluation Board Evaluation Board D06083-0-8/06(A) Rev Page 0.75 8° 0.60 0° 0.45 Package Option RU-16 ...