EVAL-ADN2850-25EBZ Analog Devices Inc, EVAL-ADN2850-25EBZ Datasheet
EVAL-ADN2850-25EBZ
Specifications of EVAL-ADN2850-25EBZ
Related parts for EVAL-ADN2850-25EBZ
EVAL-ADN2850-25EBZ Summary of contents
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FEATURES Dual-channel, 1024-position resolution 25 kΩ, 250 kΩ nominal resistance Maximum ±8% nominal resistor tolerance error Low temperature coefficient: 35 ppm/°C 2 single supply or ±2.5 V dual supply Current monitoring configurable function SPI-compatible serial interface ...
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... Added Figure 15, Figure 16, Figure 17......................................... 11 Changes to Figure 21...................................................................... 12 Changes to Theory of Operation Section.................................... 13 Changes to Figure 25...................................................................... 14 Changes to Programming Variable Resister Section ................. 19 Changes to Table 13........................................................................ 19 Changes to EVAL-ADN2850EBZ Evaluation Kit Section ........ 20 Added Gain Control Compensation Section.............................. 21 Daisy-Chain Operation ............................................................. 14 Terminal Voltage Operating Range ......................................... 15 ...
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SPECIFICATIONS ELECTRICAL CHARACTERISTICS—25 kΩ, 250 kΩ VERSIONS specifications apply to versions with a date code 1045 or later. Table 1. Parameter ...
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ADN2850 Parameter CURRENT MONITOR TERMINALS Current Sink Current Sink DYNAMIC CHARACTERISTICS Resistor Noise Density Analog Crosstalk 1 Typicals represent average readings at 25°C and V 2 Resistor position nonlinearity error (R-INL) is ...
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INTERFACE TIMING AND EEMEM RELIABILITY CHARACTERISTICS—25 kΩ, 250 kΩ VERSIONS Guaranteed by design and not subject to production test. See the Timing Diagrams section for the location of measured values. All input control voltages are specified with ...
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ADN2850 Timing Diagrams CLK CPOL = 1 HIGH OR LOW SDI t 8 SDO B24 RDY *THE EXTRA BIT THAT IS NOT DEFINED IS NORMALLY THE LSB OF THE CHARACTER PREVIOUSLY TRANSMITTED. THE CPOL = ...
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ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter V to GND GND GND Pulsed ...
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ADN2850 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 4. Pin Function Descriptions Pin No. Mnemonic Description 1 CLK Serial Input Register Clock. Shifts in one bit at a time on positive clock edges. 2 SDI Serial Data Input. Shifts in one ...
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Table 5. Pin Function Descriptions Pin No. Mnemonic Description 1 SDO Serial Data Output. Serves readback and daisy-chain functions. Command 9 and Command 10 activate the SDO output for the readback function, delayed clock pulses, depending ...
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ADN2850 TYPICAL PERFORMANCE CHARACTERISTICS 0.20 +85°C +25°C 0.15 –40°C 0.10 0.05 0 –0.05 –0.10 –0.15 –0.20 0 200 400 600 DIGITAL CODE Figure 6. R-INL vs. Code −40°C, +25°C, +85°C Overlay 0.20 +85°C +25°C –40°C 0.15 ...
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VDIO (V) Figure 12 Digital Input Voltage ± 10 0V, I (25k) = 200µ –10 I (250k) = ...
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ADN2850 CS (5V/DIV) CLK (5V/DIV) SDI (5V/DIV) Figure 18. I vs. Time when Storing Data to EEMEM DD TEST CIRCUITS Figure 20 to Figure 24 define the test conditions used in the Specifications section. DUT ...
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THEORY OF OPERATION The ADN2850 digital programmable resistor is designed to operate as a true variable resistor. The resistor wiper position is determined by the RDAC register contents. The RDAC register acts as a scratchpad register, allowing unlimited changes of ...
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ADN2850 EEMEM PROTECTION The write protect ( WP ) pin disables any changes to the scratchpad register contents, except for the EEMEM setting, which can still be restored using Instruction 1, Instruction 8, and the PR pulse. Therefore, WP can ...
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SDO-to-SDI interface may require additional time delay between subsequent devices. When two ADN2850s are daisy-chained, 48 bits of data are required. The first 24 bits (formatted 4-bit command, 4-bit address, and 16-bit data) ...
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ADN2850 In Table 7, command bits are C0 to C3, address bits are A0 to A3, Data Bit D0 to Data Bit D9 are applicable to RDAC, and D0 to D15 are applicable to EEMEM. Table 7. 24-Bit Serial Data-Word ...
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ADVANCED CONTROL MODES The ADN2850 digital resistor includes a set of user programming features to address the wide number of applications for these universal adjustment devices. Key programming features include the following: • Scratchpad programming to any desirable values • ...
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ADN2850 Using CS to Re-Execute a Previous Command Another subtle feature of the ADN2850 is that a subsequent CS strobe, without clock and data, repeats a previous command. Using Additional Internal Nonvolatile EEMEM The ADN2850 contains additional user EEMEM registers ...
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PROGRAMMING THE VARIABLE RESISTOR The nominal resistance of the RDAC between Terminal W and Terminal available with 25 kΩ and 250 kΩ with WB 1024 positions (10-bit resolution). The final digits of the part number determine ...
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... EVAL-ADN2850SDZ EVALUATION KIT Analog Devices, Inc., offers a user-friendly EVAL- ADN2850SDZ evaluation kit that can be controlled conjunction with the DSP platform. The driving program is self-contained; no programming languages or skills are needed. Rev Page Action Prepares data read from USER1 EEMEM location ...
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APPLICATIONS INFORMATION GAIN CONTROL COMPENSATION A digital resistor is commonly used in gain control such as the noninverting gain amplifier shown in Figure 34. C2 2.2pF R2 250kΩ 47kΩ 11pF V I Figure 34. Typical ...
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ADN2850 At the resonant frequency the overall phase shift is zero, and O the positive feedback causes the circuit to oscillate. With and R2 = R2A /(R2B + R ), the ...
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I and I are saturation current are V , base-emitted voltages of the diode connector transistors the thermal voltage, which is equal to k × T ...
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ADN2850 RESISTANCE TOLERANCE, DRIFT, AND TEMPERATURE COEFFICIENT MISMATCH CONSIDERATIONS In operation, such as gain control, the tolerance mismatch between the digital resistor and the discrete resistor can cause repeatability issues among various systems (see Figure 42). Because of the inherent ...
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... THE EXPOSED PAD, REFER TO THE PIN CONFIGURATION AND FUNCTION DESCRIPTIONS SECTION OF THIS DATA SHEET. 0.75 8° 0.60 0° 0.45 Package Description Package Option 16-Lead TSSOP RU-16 16-Lead TSSOP RU-16 16-Lead LFCSP_VQ CP-16-6 16-Lead LFCSP CP-16-6 16-Lead LFCSP_VQ CP-16-6 16-Lead LFCSP_VQ CP-16-6 Evaluation Board ADN2850 ...
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ADN2850 NOTES Rev Page ...
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NOTES Rev Page ADN2850 ...
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ADN2850 NOTES ©2004–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D02660-0-4/11(C) Rev Page ...