The AD5235 is a dual-channel, nonvolatile memory, digitallycontrolled potentiometer with 1024-step resolution, offeringguaranteed maximum low resistor tolerance error of ?8%.The device performs the same electronic adjustment functionas a mechanical potentiometer with enhanced resolution, solidstate reliability, and superior low temperature coefficient performance.The versatile programming of the AD5235 via anSPI?-compatible serial interface allows 16 modes of operationand adjustment including scratchpad programming, memorystoring and restoring, increment/decrement, ?6 dB/step log taperadjustment, wiper setting readback, and extra EEMEM for user-definedinformation such as memory data for other components,look-up table, or system identification information.In the scratchpad programming mode, a specific setting canbe programmed directly to the RDAC register, which sets theresistance between Terminal W and Terminal A and Terminal Wand Terminal B. This setting can be stored into the EEMEMand is restored automatically to the RDAC register duringsystem power-on.The EEMEM content can be restored dynamically or throughexternal PR strobing, and a WP function protects EEMEMcontents. To simplify the programming, the independent orsimultaneous linear-step increment or decrement commandscan be used to move the RDAC wiper up or down, one step ata time. For logarithmic ?6 dB changes in the wiper setting, theleft or right bit shift command can be used to double or halve theRDAC wiper setting.The AD5235 patterned resistance tolerance is stored in theEEMEM. The actual end-to-end resistance can, therefore, beknown by the host processor in readback mode. The host canexecute the appropriate resistance step through a softwareroutine that simplifies open-loop applications as well asprecision calibration and tolerance matching applications.The AD5235 is available in a thin, 16-lead TSSOP package.The part is guaranteed to operate over the extended industrialtemperature range of ?40?C to +85?C.Applications DWDM laser diode driver, optical supervisory systems Mechanical potentiometer replacement Instrumentation: gain, offset adjustment Programmable voltage-to-current conversion Programmable filters, delays, time constants Programmable power supply Low resolution DAC replacement Sensor calibration
Part number: EVAL-AD5235SDZ
More details from Analog Devices Inc.