AD5235BRU250-RL7 Analog Devices Inc, AD5235BRU250-RL7 Datasheet
AD5235BRU250-RL7
Specifications of AD5235BRU250-RL7
Related parts for AD5235BRU250-RL7
AD5235BRU250-RL7 Summary of contents
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FEATURES Dual-channel, 1024-position resolution 25 kΩ, 250 kΩ nominal resistance Low temperature coefficient: 35 ppm/°C Nonvolatile memory stores wiper settings Permanent memory write protection Wiper setting readback Resistance tolerance stored in EEMEM Predefined linear increment/decrement instructions Predefined ±6 dB/step log ...
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AD5235 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Functional Block Diagram .............................................................. 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Electrical Characteristics—25 kΩ, 250 kΩ Versions ............... 3 Interface Timing and EEMEM Reliability Characteristics—25 ...
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SPECIFICATIONS ELECTRICAL CHARACTERISTICS—25 kΩ, 250 kΩ VERSIONS 5 2 operated at 2.7 V single supply, except from 0°C to −40°C, where a minimum ...
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AD5235 Parameter 7 EEMEM Restore Mode Current Power Dissipation 8 5 Power Supply Sensitivity DYNAMIC CHARACTERISTICS 5, 9 Bandwidth Total Harmonic Distortion V Settling Time W Resistor Noise Density Crosstalk ( Analog Crosstalk 1 Typicals represent ...
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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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AD5235 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 = ...
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ABSOLUTE MAXIMUM RATINGS T = 25°C, unless otherwise noted. A Table 3. Parameter V to GND GND GND ...
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AD5235 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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TYPICAL PERFORMANCE CHARACTERISTICS 1.0 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 0 200 400 600 DIGITAL CODE Figure 5. INL vs. Code −40°C, +25°C, +85°C Overlay 1.0 0.8 0.6 0.4 0.2 0 –0.2 ...
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AD5235 25° 200 400 600 CODE (Decimal) Figure 11. Wiper On Resistance vs. Code ...
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CODE 0x200 –10 0x100 0x080 –20 0x040 0x020 –30 0x010 –40 0x008 0x004 –50 0x002 0x001 –60 1k 10k 100k FREQUENCY (Hz) Figure 17. Gain vs. Frequency vs. Code 250 kΩ (See Figure 31 ...
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AD5235 5V/DIV 5V/DIV 5V/DIV 4ms/DIV *SUPPLY CURRENT RETURNS TO MINIMUM POWER CONSUMPTION, IF INSTRUCTION 0 (NOP) IS EXECUTED IMMEDIATELY AFTER INSTRUCTION 1 (READ EEMEM). Figure 23. I vs. Time when Restoring Data from EEMEM DD TEST CIRCUITS Figure 25 to ...
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DUT OP42 B OFFSET GND 2.5V –15V Figure 31. Gain vs. Frequency 0. DUT I SW CODE = 0x00 0. – ...
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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 When two AD5235s are daisy-chained, 48 bits of data are required. The first 24 bits (formatted 4-bit command, 4-bit address, and 16-bit data U2, and the second 24 bits with the same format go to U1. Keep ...
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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 49 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 52. + (2.048V + SLEEP OUTPUT B REF191 C1 1µF GND ...
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First, users should select convenient values for the capacitors. To achieve maximally flat bandwidth, where Q = 0.707, let C1 be twice the size of C2 and let R1 equal R2 result, the user can adjust R1 and ...
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AD5235 RESISTANCE SCALING The AD5235 offers 25 kΩ or 250 kΩ nominal resistance. When users need lower resistance but must maintain the number of adjustment steps, they can parallel multiple devices. For example, Figure 57 shows a simple scheme of ...
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RDAC CIRCUIT SIMULATION MODEL The internal parasitic capacitances and the external capacitive loads dominate the ac characteristics of the RDACs. Configured as a potentiometer divider, the −3 dB bandwidth of the AD5235 (25 kΩ resistor) measures 125 kHz at half ...
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... R (kΩ) WB_FS AD5235BRU25 25 AD5235BRU25-RL7 25 2 AD5235BRUZ25 25 2 AD5235BRUZ25-RL7 25 AD5235BRU250 250 2 AD5235BRUZ250 250 2 AD5235BRUZ250-R7 250 EVAL-AD5235EBZ 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— ...