EVAL-ADN2850-25EBZ Analog Devices Inc, EVAL-ADN2850-25EBZ Datasheet
EVAL-ADN2850-25EBZ
Specifications of EVAL-ADN2850-25EBZ
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EVAL-ADN2850-25EBZ Summary of contents
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FEATURES Dual, 1024-Position Resolution 250 k Full-Scale Resistance Low Temperature Coefficient: 35 ppm Nonvolatile Memory Preset Maintains Wiper Settings Permanent Memory Write-Protection Wiper Settings Read Back Actual Tolerance Stored in EEMEM Linear Increment/Decrement Log ...
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ADN2850–SPECIFICATIONS ELECTRICAL CHARACTERISTICS 250 k VERSIONS Parameter DC CHARACTERISTICS RHEOSTAT MODE (Specifications apply to all RDACs) 3 Resistor Differential Nonlinearity 3 Resistor Integral Nonlinearity Resistance Temperature Coefficient Wiper Resistance Channel Resistance Matching Nominal Resistor Tolerance RESISTOR TERMINALS ...
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Parameter INTERFACE TIMING CHARACTERISTICS (apply to all parts) Clock Cycle Time (t ) CYC CS Setup Time CLK Shutdown Time to CS Rise Input Clock Pulsewidth Data Setup Time Data Hold Time CS to SDO – SPI Line Acquire CS ...
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ADN2850 TIMING DIAGRAMS CLK CPOL = SDO * SDI t 14 RDY *NOT DEFINED, BUT NORMALLY LSB OF CHARACTER PREVIOUSLY TRANSMITTED. THE CPOL = 1 MICROCONTROLLER COMMAND ALIGNS THE INCOMING DATA TO THE POSITIVE ...
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ABSOLUTE MAXIMUM RATINGS (T = 25°C, unless otherwise noted GND . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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ADN2850 SDO 1 GND 2 ADN2850BCP CHIP SCALE PACKAGE ADN2850BCP PIN FUNCTION DESCRIPTIONS Pin No. Mnemonic Description 1 SDO Serial Data Output Pin. Open-Drain output requires ...
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MSB Instruction Byte 0 RDAC EEMEM D15 D14 D13 D12 D11 D10 Command bits are C0 to ...
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ADN2850 OPERATIONAL OVERVIEW The ADN2850 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 scratch pad register which allows unlimited changes ...
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Table IV illustrates the operation of the shifting function on the individual RDAC register data bits. Each line going down the table represents a successive shift operation. Note that the left shift 12 and 13 commands were modified such ...
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ADN2850 Daisy-Chain Operation The serial data output pin (SDO) serves two purposes. It can be used to read out the contents of the wiper settings or EEMEM values using instructions 10 and 9 respectively. If these instruc- tions are not ...
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TERMINAL VOLTAGE OPERATING RANGE The ADN2850 positive V and negative V DD defines the boundary conditions for proper two-terminal program- mable resistance operation. Supply signals present on terminals W and B that exceed will be clamped by ...
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ADN2850 for data 001 . The third connection is the next tap point represent- H ( 98.8 Ω for data 002 ing R WB LSB data value increase moves the wiper up the resistor ladder ...
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DIGITAL CODE TPC 1. R-INL vs. Code Ω Overlay 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 0 ...
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ADN2850 0.5V/DIV MIDSCALE TPC 7. Memory Restore During Power-On Reset 4ms/DIV TPC 8. I vs. Time (Save) Program Mode DD 4ms/DIV SUPPLY CURRENT RETURNS TO MINIMUM POWER CONSUMPTION IF INSTRUCTION ...
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... H 00XXXX SDI B00200 H C0XXXX A0XXXX XXXXXX Analog Devices offers a user-friendly ADN2850EVAL evaluation kit that can be controlled by a personal computer through the printer port. The driving program is self-contained programming languages or skills are needed. –15– ADN2850 SDO Action XXXXXX Moves wiper 1 to double the present ...
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ADN2850 APPLICATIONS Optical Transmitter Calibration with ADN2841 Together with the multirate 2.7 Gbps Laser Diode Driver ADN2841, the ADN2850 forms an optical supervisory system where the dual programmable resistors are used to set the laser average optical power and extinction ...
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The output voltage represents the average incoming optical power. The output voltage of the log stage does not have to be accurate from device to device, as the responsivity of the photodiode will change between devices amp stage ...
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ADN2850 PIN 1 INDICATOR 0.90 MAX 0.85 NOM 16-Lead Thin Shrink Small Outline Package [TSSOP] 0.15 0.05 OUTLINE DIMENSIONS 16-Lead Frame Chip Scale Package [LFCSP Body (CP-16 5x5) Dimensions shown in millimeters 5.0 BSC SQ 0.60 ...
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Revision History Location 9/02—Data sheet changed from REV REV. B. Changes to GENERAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . ...
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