AD7651ASTZ Analog Devices Inc, AD7651ASTZ Datasheet
AD7651ASTZ
Specifications of AD7651ASTZ
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AD7651ASTZ Summary of contents
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FEATURES Throughput: 100 kSPS 16-bit resolution Analog input voltage range 2 pipeline delay Parallel and serial 5 V/3 V interface ® SPI /QSPI /MICROWIRE /DSP compatible Single 5 V supply operation Power dissipation ...
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AD7651 TABLE OF CONTENTS Specifications..................................................................................... 3 Timing Specifications....................................................................... 5 Absolute Maximum Ratings............................................................ 7 Pin Configuration and Function Descriptions............................. 8 Definitions of Specifications ......................................................... 11 Typical Performance Characteristics ........................................... 12 Circuit Information ........................................................................ 15 Converter Operation.................................................................. 15 Typical Connection Diagram.................................................... 17 ...
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SPECIFICATIONS Table 2. –40°C to +85°C, AVDD = DVDD = 5 V, OVDD = 2 5.25 V, unless otherwise noted Parameter RESOLUTION ANALOG INPUT Voltage Range Operating Input Voltage Analog Input CMRR Input Current 1 Input Impedance THROUGHPUT ...
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AD7651 Parameter DIGITAL INPUTS Logic Levels DIGITAL OUTPUTS 5 Data Format Pipeline Delay POWER SUPPLIES Specified Performance AVDD DVDD OVDD Operating Current 8 AVDD AVDD 9 10 ...
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TIMING SPECIFICATIONS Table 3. –40°C to +85°C, AVDD = DVDD = 5 V, OVDD = 2 5.25 V, unless otherwise noted Parameter Refer to Figure 26 and Figure 27 Convert Pulse Width Time between Conversions CNVST LOW to ...
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AD7651 Table 4. Serial Clock Timings in Master Read after Convert DIVSCLK[1] DIVSCLK[0] SYNC to SCLK First Edge Delay Minimum Internal SCLK Period Minimum Internal SCLK Period Maximum Internal SCLK HIGH Minimum Internal SCLK LOW Minimum SDOUT Valid Setup Time ...
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ABSOLUTE MAXIMUM RATINGS 1 Table 5. AD7651 Stress Ratings TEMP ,REF, REFBUFIN, AVDD + 0 INGND, REFGND to AGND AGND – 0.3 V Ground Voltage Differences AGND, DGND, OGND ±0.3 V Supply Voltages AVDD, ...
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AD7651 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 6. Pin Function Descriptions 1 Pin No. Mnemonic Type Description 1, 36, AGND P Analog Power Ground Pin. 41 AVDD P Input Analog Power Pin. Nominally ...
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Pin No. Mnemonic Type 1 Description DI/O When SER/PAR is LOW, this output is used as Bit 7 of the parallel port data output bus. RDC/SDIN When SER/PAR is HIGH, this input, part of the serial port, ...
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AD7651 Pin No. Mnemonic Type 1 Description Primary Analog Input with a Range 2 TEMP AO Temperature Sensor Voltage Output. 46 REFBUFIN AI/O Reference Input Voltage. The reference output and the ...
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DEFINITIONS OF SPECIFICATIONS Integral Nonlinearity Error (INL) Linearity error 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 ...
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AD7651 TYPICAL PERFORMANCE CHARACTERISTICS –1 –2 –3 –4 0 16384 32768 CODE Figure 5. Integral Nonlinearity vs. Code 140000 120000 114156 114686 100000 80000 60000 40000 20890 20000 479 7FFB 7FFC 7FFD ...
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SFDR –80 –85 –90 –95 –100 THD –105 SECOND HARMONIC –110 THIRD HARMONIC –115 –120 1 10 100 FREQUENCY (kHz) Figure 11. THD, Harmonics, and SFDR vs. Frequency SNR 87 S/[N+ –60 –50 ...
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AD7651 2.5042 2.5040 2.5038 2.5036 2.5034 2.5032 2.5030 2.5028 –40 – TEMPERATURE (°C) Figure 17. Typical Reference Output Voltage vs. Temperature –30 –26 –22 –18 –14 –10 –6 –2 2 REFERENCE ...
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CIRCUIT INFORMATION IN REF REFGND 32,768C INGND The AD7651 is a very fast, low power, single supply, precise 16-bit analog-to-digital converter (ADC). The AD7651 provides the user with an on-chip track/hold, successive approximation ADC that does not exhibit any pipeline ...
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AD7651 Transfer Functions Using the OB/ 2C digital input, the AD7651 offers two output codings: straight binary and twos complement. The LSB size is V /65536, which is about 38.15 µV. The AD7651’s ideal REF transfer characteristic is shown in ...
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TYPICAL CONNECTION DIAGRAM Figure 22 shows a typical connection diagram for the AD7651. Analog Input Figure 23 shows an equivalent circuit of the input structure of the AD7651. The two diodes, D1 and D2, provide ESD protection for the analog ...
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AD7651 Voltage Reference Input The AD7651 allows the choice of either a very low temperature drift internal voltage reference or an external 2.5 V reference. Unlike many ADCs with internal references, the internal reference of the AD7651 provides excellent performance ...
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POWER DISSIPATION VERSUS THROUGHPUT Operating currents are very low during the acquisition phase, allowing significant power savings when the conversion rate is reduced (see Figure 25 ). The AD7651 automatically reduces its power consumption at the end of each conversion ...
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AD7651 DIGITAL INTERFACE The AD7651 has a versatile digital interface; it can be interfaced with the host system by using either a serial or a parallel interface. The serial interface is multiplexed on the parallel data bus. The AD7651 digital ...
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MASTER SERIAL INTERFACE Internal Clock The AD7651 is configured to generate and provide the serial data clock SCLK when the EXT/INT pin is held LOW. The AD7651 also generates a SYNC signal to indicate to the host when the serial ...
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AD7651 SLAVE SERIAL INTERFACE External Clock The AD7651 is configured to accept an externally supplied serial data clock on the SCLK pin when the EXT/ INT pin is held HIGH. In this mode, several methods can be used to read ...
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External Discontinuous Clock Data Read After Conversion Though the maximum throughput cannot be achieved using this mode the most recommended of the serial slave modes. Figure 34 shows the detailed timing diagrams of this method. After a conversion ...
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AD7651 MICROPROCESSOR INTERFACING The AD7651 is ideally suited for traditional dc measurement applications supporting a microprocessor, and for ac signal processing applications interfacing to a digital signal processor. The AD7651 is designed to interface either with a parallel 8-bit or ...
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APPLICATION HINTS BIPOLAR AND WIDER INPUT RANGES In some applications desirable to use a bipolar or wider analog input range such as ±10 V, ± Although the AD7651 has only one ...
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AD7651 OUTLINE DIMENSIONS 1.45 1.40 1.35 0.15 0.05 ROTATED 90 ° CCW 7.00 BSC SQ PIN 1 INDICATOR TOP VIEW 1.00 12° MAX 0.85 0.80 SEATING PLANE ORDERING GUIDE Model AD7651AST AD7651ASTRL AD7651ACP AD7651ACPRL 1 EVAL-AD7651CB 2 EVAL-CONTROL BRD2 ...
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NOTES Rev Page AD7651 ...
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AD7651 NOTES © 2003 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective companies. C02964–0–9/03(0) Rev Page ...