AD7984BRMZ Analog Devices Inc, AD7984BRMZ Datasheet
AD7984BRMZ
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AD7984BRMZ Summary of contents
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FEATURES 18-bit resolution with no missing codes Throughput: 1.33 MSPS Low power dissipation: 10 1.33 MSPS INL: ±2.25 LSB maximum Dynamic range: 99.7 dB typical True differential analog input range: ± with V between ...
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AD7984 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 Application Diagram ........................................................................ 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Timing Specifications .................................................................. 5 Absolute Maximum Ratings ............................................................ 6 ESD Caution .................................................................................. 6 Pin Configurations ...
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SPECIFICATIONS VDD = 2.5 V, VIO = 2 5.5 V, REF = Table 2. Parameter RESOLUTION ANALOG INPUT Voltage Range Absolute Input Voltage Common-Mode Input Range Analog Input CMRR Leakage Current at 25°C Input Impedance ...
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AD7984 VDD = 2.5 V, VIO = 2 5.5 V, REF = Table 3. Parameter Conditions REFERENCE Voltage Range Load Current 1.33 MSPS SAMPLING DYNAMICS −3 dB Input Bandwidth Aperture Delay DIGITAL INPUTS Logic Levels ...
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TIMING SPECIFICATIONS T = −40°C to +85°C, VDD = 2. 2.63 V, VIO = 2 5.5 V, unless otherwise noted. A Table 4. Parameter Conversion Time: CNV Rising Edge to Data Available Acquisition Time Time Between ...
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AD7984 ABSOLUTE MAXIMUM RATINGS Table 5. Parameter Analog Inputs 1 IN+, IN− to GND Supply Voltage REF, VIO to GND VDD to GND VDD to VIO Digital Inputs to GND Digital Outputs to GND Storage Temperature Range Junction Temperature θ ...
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PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS REF 1 10 VDD 2 9 AD7984 IN TOP VIEW (Not to Scale) IN– GND 5 6 Figure 4. 10-Lead MSOP Pin Configuration Table 6. Pin Function Descriptions 1 Pin No. ...
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AD7984 TYPICAL PERFORMANCE CHARACTERISTICS VDD = 2.5 V, REF = 5.0 V, VIO = 3.3 V. 2.0 POSITIVE INL: +1.07LSB NEGATIVE INL: –0.73LSB 1.5 1.0 0.5 0 –0.5 –1.0 –1.5 –2.0 0 65536 131072 CODE Figure 6. Integral Nonlinearity vs. ...
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SNR 95 SINAD 90 ENOB 85 80 2.5 3.0 3.5 4.0 4.5 REFERENCE VOLTAGE (V) Figure 12. SNR, SINAD, and ENOB vs. Reference Voltage 100 –55 –35 – TEMPERATURE (°C) Figure ...
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AD7984 2.5 I VDD 2.0 1.5 1.0 I REF 0.5 I VIO 0 2.375 2.425 2.475 2.525 V VOLTAGE (V) DD Figure 18. Operating Currents vs. Supply 1.5 1.4 1.3 1 VDD VIO 1.1 1.0 0.9 0.8 ...
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TERMINOLOGY Integral Nonlinearity Error (INL) INL refers to the deviation of each individual code from a line drawn from negative full scale through positive full scale. The point used as negative full scale occurs ½ LSB before the first code ...
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AD7984 THEORY OF OPERATION IN+ 131,072C REF GND 131,072C IN– CIRCUIT INFORMATION The AD7984 is a fast, low power, single-supply, precise, 18-bit ADC using a successive approximation architecture and is capable of converting 1,330,000 samples per second (1.33 MSPS). The ...
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Transfer Functions The ideal transfer characteristic for the AD7984 is shown in Figure 22 and Table 7. 011 ... 111 011 ... 110 011 ... 101 100 ... 010 100 ... 001 100 ... 000 –FSR –FSR + 1 LSB ...
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AD7984 ANALOG INPUTS Figure 24 shows an equivalent circuit of the input structure of the AD7984. The two diodes, D1 and D2, provide ESD protection for the analog inputs, IN+ and IN−. Care must be taken to ensure that the ...
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SINGLE-TO-DIFFERENTIAL DRIVER For applications using a single-ended analog signal, either bipolar or unipolar, the ADA4941-x single-ended-to- differential driver allows for a differential input into the part. The schematic is shown in Figure 26. R1 and R2 set the attenuation ratio ...
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AD7984 DIGITAL INTERFACE Although the AD7984 has a reduced number of pins, it offers flexibility in its serial interface modes. When in CS mode, the AD7984 is compatible with SPI, QSPI, digital hosts, and DSPs. In this mode, the AD7984 ...
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CS MODE, 3-WIRE WITHOUT BUSY INDICATOR This mode is usually used when a single AD7984 is connected to an SPI-compatible digital host. The connection diagram is shown in Figure 28, and the corresponding timing is given in Figure 29. With ...
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AD7984 CS MODE, 3-WIRE WITH BUSY INDICATOR This mode is usually used when a single AD7984 is connected to an SPI-compatible digital host having an interrupt input. The connection diagram is shown in Figure 30, and the corresponding timing is ...
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CS MODE, 4-WIRE WITHOUT BUSY INDICATOR This mode is usually used when multiple AD7984s are connected to an SPI-compatible digital host. A connection diagram example using two AD7984s is shown in Figure 32, and the corresponding timing is given in ...
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AD7984 CS MODE, 4-WIRE WITH BUSY INDICATOR This mode is usually used when a single AD7984 is connected to an SPI-compatible digital host with an interrupt input and when it is desired to keep CNV, which is used to sample ...
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CHAIN MODE WITHOUT BUSY INDICATOR This mode can be used to daisy-chain multiple AD7984s on a 3-wire serial interface. This feature is useful for reducing component count and wiring connections, for example, in isolated multiconverter applications or for systems with ...
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AD7984 CHAIN MODE WITH BUSY INDICATOR This mode can also be used to daisy-chain multiple AD7984s on a 3-wire serial interface while providing a busy indicator. This feature is useful for reducing component count and wiring connections, for example, in ...
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APPLICATION HINTS LAYOUT The printed circuit board (PCB) that houses the AD7984 should be designed so that the analog and digital sections are separated and confined to certain areas of the board. The pinout of the AD7984, with its analog ...
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... SEATING PLANE ORDERING GUIDE Model Temperature Range AD7984BRMZ −40°C to +85°C AD7984BRMZ-RL7 −40°C to +85°C AD7984BCPZ-RL7 −40°C to +85°C AD7984BCPZ-RL −40°C to +85°C EVAL-AD7984CBZ EVAL-CONTROL BRD3Z RoHS compliant part. 2 The EVAL-AD7984CBZ board can be used as a standalone evaluation board or in conjunction with the EVAL-CONTROL BRD3Z for evaluation/demonstration purposes. ...