AD5235BRUZ250 Analog Devices Inc, AD5235BRUZ250 Datasheet
AD5235BRUZ250
Specifications of AD5235BRUZ250
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AD5235BRUZ250 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 SPI-compatible serial interface Nonvolatile memory stores wiper ...
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AD5235 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 3 Specifications..................................................................................... 4 Electrical Characteristics—25 kΩ, 250 kΩ Versions ............... 4 Interface Timing and EEMEM Reliability Characteristics— 25 kΩ, ...
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REVISION HISTORY 4/11—Rev Rev. D Changes to EEMEM Performance .............................. Throughout Changes to Features and General Descriptions Sections.............1 Changes to Specifications Section...................................................4 Changes to Pin 5, Pin 13, Pin 14 Descriptions ..............................9 Changes to Typical Performance Characteristics Section ...
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AD5235 SPECIFICATIONS ELECTRICAL CHARACTERISTICS—25 kΩ, 250 kΩ VERSIONS These specifications apply to 25 kΩ versions with a date code 1108 or ...
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Parameter POWER SUPPLIES Single-Supply Power Range Dual-Supply Power Range Positive Supply Current Negative Supply Current EEMEM Store Mode Current 7 EEMEM Restore Mode Current 8 Power Dissipation 5 Power Supply Sensitivity 5, 9 DYNAMIC CHARACTERISTICS Bandwidth Total Harmonic Distortion V ...
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AD5235 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 t = ...
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Timing Diagrams CLK CPOL = 1 HIGH OR LOW SDI t 8 B24* SDO t 14 RDY *THE EXTRA BIT THAT IS NOT DEFINED IS NORMALLY THE LSB OF THE CHARACTER PREVIOUSLY TRANSMITTED. THE CPOL = 1 ...
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AD5235 ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter V to GND GND GND ...
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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 bit ...
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AD5235 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 5. INL vs. Code −40°C, +25°C, +85°C Overlay 0.16 +85°C +25°C 0.14 –40°C ...
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CODE (Decimal) Figure 11. Wiper On Resistance vs. Code ...
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AD5235 3 0 – 250kΩ AB – 12kHz –3dB f –3dB – ±2. rms MIDSCALE –12 1k 10k FREQUENCY (Hz) Figure 17. −3 dB Bandwidth ...
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TIME (µs) Figure 23. Midscale Glitch Energy (5V/DIV) CLK (5V/DIV) SDI (5V/DIV) I (2mA/DIV) DD Figure 24. I vs. Time ...
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AD5235 TEST CIRCUITS Figure 27 to Figure 37 define the test conditions used in the Specifications section. NC DUT CONNECT Figure 27. Resistor Position Nonlinearity Error (Rheostat Operation; R-INL, R-DNL) ...
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DUT W V GND CONNECT Figure 35. Common-Mode Leakage Current RDAC1 RDAC2 OUT ...
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AD5235 THEORY OF OPERATION The AD5235 digital potentiometer 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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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 be ...
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AD5235 DAISY-CHAIN OPERATION The serial data output pin (SDO) serves two purposes. It can be used to read the contents of the wiper setting and EEMEM values using Instruction 10 and Instruction 9, respectively. The remaining instructions (Instruction 0 to ...
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In Table 6, 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 6. 24-Bit Serial Data-Word MSB ...
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AD5235 ADVANCED CONTROL MODES The AD5235 digital potentiometer 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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Using CS to Re-Execute a Previous Command Another subtle feature of the AD5235 is that a subsequent CS strobe, without clock and data, repeats a previous command. Using Additional Internal Nonvolatile EEMEM The AD5235 contains additional user EEMEM registers for ...
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AD5235 PROGRAMMING THE VARIABLE RESISTOR Rheostat Operation The nominal resistance of the RDAC between Terminal A and Terminal available with 25 kΩ and 250 kΩ with AB 1024 positions (10-bit resolution). The final digits of the ...
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Because the AD5235 can also be supplied by dual supplies, the general equation defining the output voltage ground for any given input voltages applied to Terminal A and Terminal × ...
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AD5235 APPLICATIONS INFORMATION BIPOLAR OPERATION FROM DUAL SUPPLIES The AD5235 can be operated from ±2.5 V dual supplies, which enable control of ground referenced ac signals or bipolar operation. AC signals as high as V and V can be applied ...
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BIPOLAR PROGRAMMABLE GAIN AMPLIFIER For applications requiring bipolar gain, Figure 51 shows one implementation. Digital Potentiometer U1 sets the adjustment range; the wiper voltage (V ) can, therefore, be programmed W2 between V and − given U2 setting. ...
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AD5235 PROGRAMMABLE CURRENT SOURCE A programmable current source can be implemented with the circuit shown in Figure 54. + (2.048V + SLEEP OUTPUT B REF191 C1 1µF GND ...
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PROGRAMMABLE LOW-PASS FILTER In analog-to-digital conversions (ADCs common to include an antialiasing filter to band limit the sampling signal. Therefore, the dual-channel AD5235 can be used to construct a second-order Sallen-Key low-pass filter, as shown in Figure 56. ...
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AD5235 OPTICAL TRANSMITTER CALIBRATION WITH ADN2841 The AD5235, together with the multirate 2.7 Gbps laser diode driver, ADN2841, forms an optical supervisory system in which the dual digital potentiometers can be used to set the laser average optical power and ...
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RESISTANCE TOLERANCE, DRIFT, AND TEMPERATURE COEFFICIENT MISMATCH CONSIDERATIONS In rheostat mode operation, such as gain control, the tolerance mismatch between the digital potentiometer and the discrete resistor can cause repeatability issues among various systems (see Figure 62). Because of the ...
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... AB AD5235BRUZ25 25 AD5235BRUZ25-RL7 25 AD5235BRUZ250 250 AD5235BRUZ250-R7 250 EVAL-AD5235SDZ RoHS Compliant Part. 2 Line 1 contains the ADI logo followed by the date code, YYWW. Line 2 contains the model number followed by the end-to-end resistance value (note 250 kΩ). —OR— Line 1 contains the model number. Line 2 contains the ADI logo followed by the end-to-end resistance value. Line 3 contains the date code, YYWW. ...
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NOTES Rev Page AD5235 ...
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AD5235 NOTES ©2004–2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D02816-0-4/11(D) Rev Page ...