AD7986BCPZ Analog Devices Inc, AD7986BCPZ Datasheet
AD7986BCPZ
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AD7986BCPZ Summary of contents
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FEATURES 18-bit resolution with no missing codes Throughput: 2 MSPS (TURBO = high), 1.5 MSPS (TURBO = low) Low power dissipation MSPS, with external reference MSPS with internal reference INL: ±1 LSB ...
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AD7986 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 Configuration ...
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SPECIFICATIONS AVDD = DVDD = 2.5 V, BVDD = 5 V, VIO = 1 2 Table 2. Parameter RESOLUTION ANALOG INPUT Voltage Range Absolute Input Voltage Common-Mode Input Range Analog Input CMRR Leakage Current at 25°C ...
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AD7986 AVDD = DVDD = 2.5 V, BVDD = 5 V, VIO = 1 2 Table 3. Parameter Conditions INTERNAL REFERENCE PDREF = low Output Voltage T = 25°C A Temperature Drift −40°C to +85°C Line ...
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TIMING SPECIFICATIONS AVDD = DVDD = 2.5 V, BVDD = 5 V, VIO = 1 2 Table 4. Parameter Conversion Time: CNV Rising Edge to Data Available (Turbo Mode/Normal Mode) Acquisition Time Time Between Conversions (Turbo ...
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AD7986 ABSOLUTE MAXIMUM RATINGS Table 5. Parameter Analog Inputs 1 IN+, IN− to GND Supply Voltage REF, BVDD to GND, REFGND AVDD, DVDD, VIO to GND AVDD and DVDD to VIO Digital Inputs to GND Digital Outputs to GND Storage ...
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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 6. Pin Function Descriptions 1 Pin No. Mnemonic Type Description 1, 2 REF AI Reference Output/Input Voltage. When PDREF = low, the internal reference and buffer are enabled, producing 4.096 V on this pin. ...
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AD7986 1 Pin No. Mnemonic Type Description 16 AVDD P Input Analog Power. Nominally at 2.5 V. 17,18 AGND P Analog Power Ground. 19 BVDD P Reference buffer power. Nominally 5 external reference buffer is used to ...
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TYPICAL PERFORMANCE CHARACTERISTICS AVDD = DVDD = VIO = 2.5 V, BVDD = 5 2.5 POSITIVE INL = +1.57LSB 2.0 NEGATIVE INL = –1.25LSB 1.5 1.0 0.5 0 –0.5 –1.0 –1.5 –2.0 –2.5 0 65,536 131,072 CODE Figure ...
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AD7986 0 –20 –40 –60 –80 –100 –120 –140 –160 –180 –200 0 200k 400k 600k FREQUENCY (Hz) Figure 11. FFT Plot (External Reference) 100 SNR 95 SINAD ENOB 2.5 3.0 3.5 4.0 REFERENCE VOLTAGE (V) Figure ...
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INPUT LEVEL (dB) Figure 17. SNR vs. Input Level 3.0 I REF 2.5 2.0 I AVDD 1.5 I DVDD 1.0 I ...
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AD7986 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 ...
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THEORY OF OPERATION IN+ 131,072C REF REFGND 131,072C IN– CIRCUIT INFORMATION The AD7986 is a fast, low power, single-supply, precise, 18-bit ADC using a successive approximation architecture. The AD7986 features different modes to optimize performance according to the application. In ...
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AD7986 Transfer Functions The ideal transfer characteristic for the AD7986 is shown in Figure 22 and Table 7. 011 ... 111 011 ... 110 011 ... 101 100 ... 010 100 ... 001 100 ... 000 –FSR –FSR + 1 ...
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ANALOG INPUTS Figure 24 shows an equivalent circuit of the input structure of the AD7986. The two diodes, D1 and D2, provide ESD protection for the analog inputs, IN+ and IN−. Care must be taken to ensure that the analog ...
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AD7986 VOLTAGE REFERENCE INPUT The AD7986 allows the choice of a very low temperature drift internal voltage reference, an external reference external buffered reference. The internal reference of the AD7986 provides excellent performance and can be used in ...
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DIGITAL INTERFACE Although the AD7986 has a reduced number of pins, it offers flexibility in its serial interface modes. When in CS mode, the AD7986 is compatible with SPI, MICROWIRE™, QSPI™, and digital hosts. In this mode, the AD7986 can ...
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AD7986 DATA READING OPTIONS There are three different data reading options for the AD7986. There is the option to read during conversion, to split the read across acquisition and conversion (see Figure 27 and Figure 28), and in normal mode, ...
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CS MODE, 3-WIRE WITHOUT BUSY INDICATOR This mode is usually used when a single AD7986 is connected to an SPI-compatible digital host. The connection diagram is shown in Figure 25, and the corresponding timing is given in Figure 26. With ...
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AD7986 CS MODE, 3-WIRE WITH BUSY INDICATOR This mode is usually used when a single AD7986 is connected to an SPI-compatible digital host having an interrupt input only available in normal conversion mode (TURBO = low). The connection ...
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CS MODE, 4-WIRE WITHOUT BUSY INDICATOR This mode is usually used when multiple AD7986 devices are connected to an SPI-compatible digital host. A connection diagram example using two AD7986 devices is shown in Figure 29, and the corresponding timing is ...
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AD7986 CS MODE, 4-WIRE WITH BUSY INDICATOR This mode is usually used when a single AD7986 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 AD7986 devices on a 3-wire serial interface only available in normal conver- sion mode (TURBO = low). This feature is useful for reducing component count ...
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AD7986 CHAIN MODE WITH BUSY INDICATOR This mode can also be used to daisy-chain multiple AD7986 devices on a 3-wire serial interface while providing a busy indicator. This feature is useful for reducing component count and wiring connections, for example, ...
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APPLICATION HINTS LAYOUT The printed circuit board (PCB) that houses the AD7986 should be designed so that the analog and digital sections are separated and confined to certain areas of the board. The pinout of the AD7986, with its analog ...
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AD7986 REF GND 5V EXTERNAL REFERENCE (ADR435 OR ADR445) REF REF CREF GND GND BVDD REF REF PADDLE 1 2 GND 3 GND GND GND Figure 37. Example Layout of the AD7986 (Top Layer) BVDD AVDD CBVDD ...
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... SEATING PLANE ORDERING GUIDE Model Temperature Range AD7986BCPZ −40°C to +85°C AD7986BCPZ-RL7 −40°C to +85°C EVAL-AD7986EBZ EVAL-CED1Z RoHS Compliant Part. 2 The EVAL-AD7986EBZ can be used as a standalone evaluation board or in conjunction with the EVAL-CED1Z for evaluation/demonstration purposes. 3 The EVAL-CED1Z allows control and communicate with all Analog Devices evaluation boards ending in the EB designator. ...
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AD7986 NOTES ©2009–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D07956-0-3/11(B) Rev Page ...