The AD52521 is a dual-channel, I2C, nonvolatile memory,digitally controlled potentiometer with 256 positions. These devices perform the same electronic adjustmentfunctions as mechanical potentiometers, trimmers, andvariable resistors. The parts’ versatile programmability allowsmultiple modes of operation, including read/write access in theRDAC and EEMEM registers, increment/decrement of resistance,resistance changes in ±6 dB scales, wiper setting readback,and extra EEMEM for storing user-defined information, such asmemory data for other components, look-up table, or systemidentification information.The AD5251/AD5252 allow the host I2C controllers to writeany of the 64-/256-step wiper settings in the RDAC registersand store them in the EEMEM. Once the settings are stored,they are restored automatically to the RDAC registers at systempower-on; the settings can also be restored dynamically.The AD5251/AD5252 provide additional increment,decrement, +6 dB step change, and –6 dB step change insynchronous or asynchronous channel update mode. Theincrement and decrement functions allow stepwise linearadjustments, with a ± 6 dB step change equivalent to doublingor halving the RDAC wiper setting. These functions are usefulfor steep-slope, nonlinear adjustments, such as white LEDbrightness and audio volume control.The AD5251/AD5252 have a patented resistance-tolerancestoring function that allows the user to access the EEMEM andobtain the absolute end-to-end resistance values of the RDACsfor precision applications.The AD5251/AD5252 are available in TSSOP-14 packages.AD5251 has only 50 kΩ resistance options and AD5252 isavailable in 1 kΩ, 10 kΩ, 50 kΩ, and 100 kΩ options. All partsare guaranteed to operate over the –40°C to +105°C extendedindustrial temperature range.APPLICATIONS Mechanical potentiometer replacement General-purpose DAC replacement LCD panel VCOM adjustment White LED brightness adjustment RF base station power amp bias control Programmable gain and offset control Programmable voltage-to-current conversion Programmable power supply Sensor calibrations1 Protected by U.S. Patent 7,688,240.

The AD5290 is one of the few high voltage, high performance, and compact digital potentiometers1 in the market at present. This device can be used as a programmable resistor or resistor divider. The AD5290 performs the same electronic adjustment function as mechanical potentiometers, variable resistors, and trimmers, with enhanced resolution, solid-state reliability, and superior temperature stability.With digital rather than manual control, the AD5290 provides layout flexibility and allows closed-loop dynamic controllability.The AD5290 is available in MSOP-10 package and has 10 kΩ, 50 kΩ, and 100 kΩ options. All parts are guaranteed to operate over the –40°C to +125°C extended automotive temperature range.Applications High voltage DAC Programmable power supply Programmable gain and offset adjustment Programmable filters and delays Actuator control Audio volume control Mechanical potentiometer replacement1 The RDAC segmentation is protected by U.S. Patent Number 5,495,245.

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

The AD5259 provides a compact, nonvolatile LFCSP-10 (3 mm x 3 mm) or MSOP-10 (3 mm x 4.9 mm) packaged solution for 256-position adjustment applications. These devices perform the same electronic adjustment function as mechanical potentiometers or variable resistors, but with enhanced resolution and solid-state reliability. The terms digital potentiometer, VR (variable resistor), and RDAC are used interchangeably.The wiper settings are controllable through an I2C-compatible digital interface that is also used to read back the wiper register and EEPROM content. Resistor tolerance is also stored within EEPROM, providing an end-to-end tolerance accuracy of 0.1%.A separate VLOGIC pin delivers increased interface flexibility. For users who need multiple parts on one bus, Address Bit AD0 and Address Bit AD1 allow up to four devices on the same busAPPLICATIONS LCD panel VCOM adjustment LCD panel brightness and contrast control Mechanical potentiometer replacement in new designs Programmable power supplies RF amplifier biasing Automotive electronics adjustment Gain control and offset adjustment Fiber to the home systems Electronics level settings

The AD5259 provides a compact, nonvolatile LFCSP-10 (3 mm x 3 mm) or MSOP-10 (3 mm x 4.9 mm) packaged solution for 256-position adjustment applications. These devices perform the same electronic adjustment function as mechanical potentiometers or variable resistors, but with enhanced resolution and solid-state reliability. The terms digital potentiometer, VR (variable resistor), and RDAC are used interchangeably.The wiper settings are controllable through an I2C-compatible digital interface that is also used to read back the wiper register and EEPROM content. Resistor tolerance is also stored within EEPROM, providing an end-to-end tolerance accuracy of 0.1%.A separate VLOGIC pin delivers increased interface flexibility. For users who need multiple parts on one bus, Address Bit AD0 and Address Bit AD1 allow up to four devices on the same busAPPLICATIONS LCD panel VCOM adjustment LCD panel brightness and contrast control Mechanical potentiometer replacement in new designs Programmable power supplies RF amplifier biasing Automotive electronics adjustment Gain control and offset adjustment Fiber to the home systems Electronics level settings

The AD5259 provides a compact, nonvolatile LFCSP-10 (3 mm x 3 mm) or MSOP-10 (3 mm x 4.9 mm) packaged solution for 256-position adjustment applications. These devices perform the same electronic adjustment function as mechanical potentiometers or variable resistors, but with enhanced resolution and solid-state reliability. The terms digital potentiometer, VR (variable resistor), and RDAC are used interchangeably.The wiper settings are controllable through an I2C-compatible digital interface that is also used to read back the wiper register and EEPROM content. Resistor tolerance is also stored within EEPROM, providing an end-to-end tolerance accuracy of 0.1%.A separate VLOGIC pin delivers increased interface flexibility. For users who need multiple parts on one bus, Address Bit AD0 and Address Bit AD1 allow up to four devices on the same busAPPLICATIONS LCD panel VCOM adjustment LCD panel brightness and contrast control Mechanical potentiometer replacement in new designs Programmable power supplies RF amplifier biasing Automotive electronics adjustment Gain control and offset adjustment Fiber to the home systems Electronics level settings

The AD8400 / AD8402 / AD8403 provide a single, dual or quad channel, 256 position digitally controlled variable resistor (VR) device. These devices perform the same electronic adjustment function as a potentiometer or variable resistor. The AD8400 contains a single variable resistor in the compact SO-8 package. The AD8402 contains two independent variable resistors in saving SO-14 surface mount package. The AD8403 contains four independent variable resistors in 24-lead PDIP, SOIC and TSSOP packages. Each part contains a fixed resistor with a wiper contact that taps the fixed resistor value at a point determined by a digital code loaded into the controlling serial input register. The resistance between the wiper and either endpoint of the fixed resistor varies linearly with respect to the digital code transferred into the VR latch. Each variable resistor offers a completely programmable value of resistance, between the A terminal and the wiper or the B terminal and the wiper. The fixed A to B terminal resistance of 1 kOhm, 10 kOhm, 50 kOhm or 100 kOhm has a ±1% channel-to-channel matching tolerance with a nominal temperature coefficient of 500 ppm/°C. A unique switching circuit minimizes the high glitch inherent in traditional switched resistor designs avoiding any make-before-break or break-before-make operation.Each VR has its own VR latch that holds its programmed resistance value. These VR latches are updated from an SPI compatible serial-to-parallel shift register that is loaded from a standard 3-wire serial-input digital interface. Ten data bits make up the data word clocked into the serial input register. The data word is decoded where the first two bits determine the address of the VR latch to be loaded, the last eight bits are data. A serial data output pin at the opposite end of the serial register allows simple daisy-chaining in multiple VR applications without additional external decoding logic.APPLICATIONS Mechanical potentiometer replacement Programmable filters, delays, time constants Volume control, panning Line impedance matching Power supply adjustment

The AD8400/AD8402/AD8403 provide a single, dual or quad channel, 256 position digitally controlled variable resistor (VR) device. These devices perform the same electronic adjustment function as a potentiometer or variable resistor. The AD8400 contains a single variable resistor in the compact SO-8 package. The AD8402 contains two independent variable resistors in saving SO-14 surface mount package. The AD8403 contains four independent variable resistors in 24-lead PDIP, SOIC and TSSOP packages. Each part contains a fixed resistor with a wiper contact that taps the fixed resistor value at a point determined by a digital code loaded into the controlling serial input register. The resistance between the wiper and either endpoint of the fixed resistor varies linearly with respect to the digital code transferred into the VR latch. Each variable resistor offers a completely programmable value of resistance, between the A terminal and the wiper or the B terminal and the wiper. The fixed A to B terminal resistance of 1 kOhm, 10 kOhm, 50 kOhm or 100 kOhm has a ±1% channel-to-channel matching tolerance with a nominal temperature coefficient of 500 ppm/°C. A unique switching circuit minimizes the high glitch inherent in traditional switched resistor designs avoiding any make-before-break or break-before-make operation.Each VR has its own VR latch that holds its programmed resistance value. These VR latches are updated from an SPI compatible serial-to-parallel shift register that is loaded from a standard 3-wire serial-input digital interface. Ten data bits make up the data word clocked into the serial input register. The data word is decoded where the first two bits determine the address of the VR latch to be loaded, the last eight bits are data. A serial data output pin at the opposite end of the serial register allows simple daisy-chaining in multiple VR applications without additional external decoding logic.

The AD8400/AD8402/AD8403 provide a single, dual or quad channel, 256 position digitally controlled variable resistor (VR) device. These devices perform the same electronic adjustment function as a potentiometer or variable resistor. The AD8400 contains a single variable resistor in the compact SO-8 package. The AD8402 contains two independent variable resistors in saving SO-14 surface mount package. The AD8403 contains four independent variable resistors in 24-lead PDIP, SOIC and TSSOP packages. Each part contains a fixed resistor with a wiper contact that taps the fixed resistor value at a point determined by a digital code loaded into the controlling serial input register. The resistance between the wiper and either endpoint of the fixed resistor varies linearly with respect to the digital code transferred into the VR latch. Each variable resistor offers a completely programmable value of resistance, between the A terminal and the wiper or the B terminal and the wiper. The fixed A to B terminal resistance of 1 kOhm, 10 kOhm, 50 kOhm or 100 kOhm has a ±1% channel-to-channel matching tolerance with a nominal temperature coefficient of 500 ppm/°C. A unique switching circuit minimizes the high glitch inherent in traditional switched resistor designs avoiding any make-before-break or break-before-make operation.Each VR has its own VR latch that holds its programmed resistance value. These VR latches are updated from an SPI compatible serial-to-parallel shift register that is loaded from a standard 3-wire serial-input digital interface. Ten data bits make up the data word clocked into the serial input register. The data word is decoded where the first two bits determine the address of the VR latch to be loaded, the last eight bits are data. A serial data output pin at the opposite end of the serial register allows simple daisy-chaining in multiple VR applications without additional external decoding logic.

The AD9835 is a numerically-controlled oscillator employing a phase accumulator, a COS lookup table, and a 10-bit digital-to-analog converter integrated on a single CMOS chip. Modulation capabilities are provided for phase modulation and frequency modulation.Clock rates of up to 50 MHz are supported. Frequency accuracycan be controlled to one part in 4 billion. Modulation is effected by loading registers through the serial interface. A power-down bit allows the user to power down the AD9835 when it is not in use, the power consumption reduces to 1.75 mW.The part is available in a 16-lead TSSOP package.APPLICATIONS Frequency stimulus/waveform generation Frequency phase tuning and modulation Low power RF/communications systems Liquid and gas flow measurement Sensory applications: proximity, motion, and defect detection Test and medical equipment