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 AD7891 is an 8-channel, 12-bit data acquisition system with a choice of either parallel or serial interface structure. The part contains an input multiplexer, an on-chip track/hold amplifier, a high speed 12-bit ADC, a 2.5 V reference, and a high speed interface. The part operates from a single 5 V supply and accepts a variety of analog input ranges across two models, the AD7891-1 (±5 V and ±10 V) and the AD7891-2 (0 V to +2.5 V, 0 V to +5 V, and ±2.5 V).The AD7891 provides the option of either a parallel or serial interface structure determined by the MODE pin. The part has standard control inputs and fast data access times for both the serial and parallel interfaces, ensuring easy interfacing to modern microprocessors, microcontrollers, and digital signal processors.In addition to the traditional dc accuracy specifications, such as linearity, full-scale and offset errors, the part is also specified for dynamic performance parameters, including harmonic distortion and signal-to-noise ratio.Power dissipation in normal mode is 82 mW typical; in the standby mode, this is reduced to 75 mW typ. The part is available in a 44-terminal MQFP and a 44-lead PLCC.PRODUCT HIGHLIGHTS The AD7891 is a complete monolithic 12-bit data acquisition system that combines an 8-channel multiplexer, 12-bit ADC, 2.5 V reference, and track/hold amplifier on a single chip. The AD7891-2 features a conversion time of 1.6 ms and an acquisition time of 0.4 ms. This allows a sample rate of 500 kSPS when sampling one channel and 62.5 kSPS when channel hopping. These sample rates can be achieved using either a software or hardware convert start. The AD7891-1 has an acquisition time of 0.6 ms when using a hardware convert start and an acquisition time of 0.7 ms when using a software convert start. These acquisition times allow sample rates of 454.5 kSPS and 435 kSPS, respectively, for hardware and software convert start. Each channel on the AD7891 has overvoltage protection. This means an overvoltage on an unselected channel does not affect the conversion on a selected channel. The AD7891-1 can withstand overvoltages of ±17 V.APPLICATIONS Data Acquisition Systems Motor Control Mobile Communication Base Stations Instrumentation

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 AD5231 is a nonvolatile memory, digitally controlled potentiometer with 1024-step resolution. The device performs the same electronic adjustment function as a mechanical potentiometer with enhanced resolution, solid state reliability, and remote controllability. The AD5231 has versatile programming that uses a standard 3-wire serial interface for 16 modes of operation and adjustment, including scratchpad programming, memory storing and restoring, increment/decrement, ±6 dB/step log taper adjustment, wiper setting readback, and extra EEMEM for user-defined information, such as memory data for other components, look-up table, or system identification information.In scratchpad programming mode, a specific setting can be programmed directly to the RDAC register that sets the resistance between Terminals W–A and Terminals W–B. This setting can be stored into the EEMEM and is transferred automatically to the RDAC register during system power-on.The EEMEM content can be restored dynamically or through external PR strobing, and a WP function protects EEMEM contents. To simplify the programming, the linear-step increment or decrement commands can be used to move the RDAC wiper up or down, one step at a time. The ±6 dB step commands can be used to double or half the RDAC wiper setting.The AD5231 is available in a 16-lead TSSOP. The part is guaranteed to operate over the extended industrial temperature range of −40°C to +85°C.APPLICATIONS 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 AD5231 is a nonvolatile memory, digitally controlled potentiometer with 1024-step resolution. The device performs the same electronic adjustment function as a mechanical potentiometer with enhanced resolution, solid state reliability, and remote controllability. The AD5231 has versatile programming that uses a standard 3-wire serial interface for 16 modes of operation and adjustment, including scratchpad programming, memory storing and restoring, increment/decrement, ±6 dB/step log taper adjustment, wiper setting readback, and extra EEMEM for user-defined information, such as memory data for other components, look-up table, or system identification information.In scratchpad programming mode, a specific setting can be programmed directly to the RDAC register that sets the resistance between Terminals W–A and Terminals W–B. This setting can be stored into the EEMEM and is transferred automatically to the RDAC register during system power-on.The EEMEM content can be restored dynamically or through external PR strobing, and a WP function protects EEMEM contents. To simplify the programming, the linear-step increment or decrement commands can be used to move the RDAC wiper up or down, one step at a time. The ±6 dB step commands can be used to double or half the RDAC wiper setting.The AD5231 is available in a 16-lead TSSOP. The part is guaranteed to operate over the extended industrial temperature range of −40°C to +85°C.APPLICATIONS 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 AD5258 provides a compact, nonvolatile 3 mm × 4.9 mm packaged solution for 64-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 wiper settings are controllable through an I2C-compatible digital interface that is also used to read back the wiper register and EEPROM content in addition, resistor tolerance is stored within EEPROM, providing an end-to-end tolerance accuracy of 0.1%. There is also a software write protection function that ensures data cannot be written to the EEPROM register.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 bus.APPLICATIONS 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 AD5258 provides a compact, nonvolatile 3 mm × 4.9 mm packaged solution for 64-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 wiper settings are controllable through an I2C-compatible digital interface that is also used to read back the wiper register and EEPROM content in addition, resistor tolerance is stored within EEPROM, providing an end-to-end tolerance accuracy of 0.1%. There is also a software write protection function that ensures data cannot be written to the EEPROM register.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 bus.APPLICATIONS 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 AD637 is a complete, high accuracy, rms-to-dc converter that computes the true rms value of any complex waveform. It offers performance that is unprecedented in integrated circuit rms-to-dc converters and comparable to discrete and modular techniques in accuracy, bandwidth, and dynamic range. The AD637 computes the true root mean square, mean square, or absolute value of any complex ac (or ac plus dc) input waveform and gives an equivalent dc output voltage. The true rms value of a waveform is more useful than an average rectified signal because it relates directly to the power of the signal. The rms value of a statistical signal relates to the standard deviation of the signal.Superior crest factor compensation permits measurements of signals with crest factors of up to 10 with less than 1% additional error. The wide bandwidth of the AD637 permits the measurement of signals up to 600 kHz with inputs of 200 mV rms and up to 8 MHz when the input levels are above 1 V rms.Direct dB value of the rms output with a range of 60 dB is available on a separate pin. An externally programmed reference current allows the user to select the 0 dB reference voltage to correspond to any level between 0.1 V and 2.0 V rms.A chip select connection on the AD637 permits the user to decrease the supply current from 2.2 mA to 350 µA during periods when the rms function is not in use. This feature facilitates the addition of precision rms measurement to remote or handheld applications where minimum power consumption is critical. In addition, when the AD637 is powered down, the output goes to a high impedance state. This allows several AD637s to be tied together to form a wideband true rms multiplexer.The input circuitry of the AD637 is protected from overload voltages in excess of the supply levels. The inputs are not damaged by input signals if the supply voltages are lost.The AD637 is laser wafer trimmed to achieve rated performance without external trimming. The only external component required is a capacitor that sets the averaging period. The value of this capacitor also determines low frequency accuracy, ripple level, and settling time.The on-chip buffer amplifier is used either as an input buffer or in an active filter configuration. The filter can be used to reduce the amount of ac ripple, thereby increasing accuracy.The AD637 is available in accuracy Grade J and Grade K for commercial temperature range (0°C to 70°C) applications, accuracy Grade A and Grade B for industrial range (−40°C to +85°C) applications, and accuracy Grade S rated over the −55°C to +125°C temperature range. All versions are available in hermetically sealed, 14-lead SBDIP, 14-lead CERDIP, and 16-lead SOIC_W packages.

The AD7142 and AD7142-1 are integrated capacitance-to-digital converters (CDCs) with on-chip environmental calibration for use in systems requiring a novel user input method. The AD7142 and AD7142-1 can interface to external capacitance sensors implementing functions such as capacitive buttons, scroll bars, or wheels.The CDC has 14 inputs channeled through a switch matrix to a 16-bit, 250 kHz sigma-delta (∑-Δ) capacitance-to-digital converter. The CDC is capable of sensing changes in the capacitance of the external sensors and uses this information to register a sensor activation. The external sensors can be arranged as a series of buttons, as a scroll bar or wheel, or as a combination of sensor types. By programming the registers, the user has full control over the CDC setup. High resolution sensors require minor software to run on the host processor. The AD7142 and AD7142-1 have on-chip calibration logic to account for changes in the ambient environment. The calibration sequence is performed automatically and at continuous intervals, when the sensors are not touched. This ensures that there are no false or nonregistering touches on the external sensors due to a changing environment.The AD7142 has an SPI-compatible serial interface, and the AD7142-1 has an I2C-compatible serial interface. Both parts have an interrupt output, as well as a general-purpose input/ output (GPIO). The AD7142 and AD7142-1 are available in a 32-lead, 5 mm × 5 mm LFCSP_VQ and operate from a 2.6 V to 3.6 V supply. The operating current consumption is less than 1 mA, falling to 50 μA in low power mode (conversion interval of 400 ms).ApplicationsPersonal music and multimedia playersCell phonesDigital still camerasSmart hand-held devicesTelevision, A/V, and remote controlsGaming consoles