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 ADE7754 is the electricity industry's first digitally calibrated, multi-function energy measurement IC programmable for all types of 3-phase grid configurations. This single chip solution measures active and apparent energy and provides a serial port interface and a pulse output. The ADE7754 transducer interface uses three fully differential current inputs and three single-ended voltage inputs. The six ADC’s digitize the signals so that all signal processing is done in the digital domain for superior stability and accuracy. The ADE7754 includes reference circuitry, temperature sensor, and all the signal processing required to perform active and apparent energy measurement as well as RMS calculation on all current and voltage channels. Additional power quality measurements are included.The ADE7754 surpasses the IEC61036/60687 accuracy requirements and provides an SPI interface for digital calibration and reading register data.The ADE7754 is available in 24-lead SOIC package.NOTE: If your application requires the measurement of reactive energy and information per phase, the ADE7758 is recommended.

The ADE7757 is an accurate electrical energy measurement integrated circuit. It is a pin reduction version of ADE7755 with an enhancement of a precise oscillator circuit that serves as a clock source to the chip. The ADE7757 eliminates the cost of an external crystal or resonator, thus reducing the overall cost of a meter built with this IC. The chip directly interfaces with shunt resistor.The ADE7757 provides instantaneous and average real power based on line current and voltage. The part specifications surpass the accuracy requirements as quoted in the IEC61036 standard. The only analog circuitry used in the ADE7757 is in the ADCs and reference circuit. All other signal processing (e.g., multiplication and filtering) is carried out in the digital domain. This approach provides superior stability and accuracy over extremes in environmental conditions and over time.The small analog input full-scale allows the chip to interface to low value shunt resistances without losing dynamic range. The ADE7757 is available in 16-lead SOIC narrow-body package.The Application Note AN-679 can be used as a basis for a description of an IEC61036 low cost, watt-hour meter reference design.NOTE: For polyphase system designs, the ADE7752A is recommended.

The AD5161 provides a compact 3 mm × 4.9 mm packagedsolution for 256-position adjustment applications. Thesedevices perform the same electronic adjustment function asmechanical potentiometers or variable resistors, with enhancedresolution, solid-state reliability, and superior low temperaturecoefficient performance.The wiper settings are controllable through a pin selectable SPIor I2C compatible digital interface, which can also be used toread back the wiper register content. When the SPI mode isused, the device can be daisy-chained (SDO to SDI), allowingseveral parts to share the same control lines. In the I2C mode, address pin AD0 can be used to place up to two devices on thesame bus. In this same mode, command bits are available toreset the wiper position to midscale or to shut down the deviceinto a state of zero power consumption.Operating from a 2.7 V to 5.5 V power supply and consumingless than 5 μA allows for usage in portable battery-operatedapplications.APPLICATIONS Mechanical potentiometer replacement in new designs Transducer adjustment of pressure, temperature, position, chemical, and optical sensors RF amplifier biasing Gain control and offset adjustment 

The AD5207 provides a dual channel, 256 position, digitally controlled variable resistor (VR) device. These devices perform the same electronic adjustment function as a potentiometer or variable resistor. Each channel of the AD5207 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 SPI compatible serial-input register. The resistance between the wiper and either end point of the fixed resistor varies linearly with respect to the digital code transferred into the VR latch. The 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 10K, 50K or 100K ohms 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 and avoids any make-before-break or break-before-make operation. The AD5207 is available in 1.1 mm thin TSSOP-14 package, which is suitable for PCMCIA applications.APPLICATIONS Mechanical Potentiometer Replacement Stereo Channel Audio Level Control Instrumentation: Gain, Offset Adjustment Programmable Voltage-to-Current Conversion Programmable Filters, Delays, Time Constants Line Impedance Matching Automotive Electronics Adjustment

The AD5232 device provides a nonvolatile, dual-channel, digitally controlled variable resistor (VR) with 256-position resolution. This device performs the same electronic adjustment function as a mechanical potentiometer with enhanced resolution, solid state reliability, and superior low temperature coefficient performance. The versatile programming of the AD5232, performed via a microcontroller, allows multiple modes of operation and adjustment.In the direct program mode, a predetermined setting of the RDAC registers (RDAC1 and RDAC2) can be loaded directly from the microcontroller. Another important mode of operation allows the RDACx register to be refreshed with the setting previously stored in the corresponding EEMEM register (EEMEM1 and EEMEM2). When changes are made to the RDACx register to establish a new wiper position, the value of the setting can be saved into the EEMEMx register by executing an EEMEM save operation. After the settings are saved in the EEMEMx register, these values are automatically transferred to the RDACx register to set the wiper position at system power-on. Such operation is enabled by the internal preset strobe. The preset strobe can also be accessed externally.All internal register contents can be read via the serial data output (SDO). This includes the RDAC1 and RDAC2 registers, the corresponding nonvolatile EEMEM1 and EEMEM2 registers, and the 14 spare USER EEMEM registers that are available for constant storage.The basic mode of adjustment is the increment and decrement command instructions that control the wiper position setting register (RDACx). An internal scratch pad RDACx register can be moved up or down one step of the nominal resistance between Terminal A and Terminal B. This step adjustment linearly changes the wiper to Terminal B resistance (RWB) by one position segment of the device’s end-to-end resistance (RAB). For exponential/ logarithmic changes in wiper setting, a left/right shift command instruction adjusts the levels in ±6 dB steps, which can be useful for audio and light alarm applications.The AD5232 is available in a thin, 16-lead TSSOP package. All parts are guaranteed to operate over the extended industrial temperature range of −40°C to +85°C. An evaluation board, the EVAL-AD5232-10EBZ, is available.APPLICATIONS Mechanical potentiometer replacement Instrumentation: gain and offset adjustment Programmable voltage-to-current conversion Programmable filters, delays, and time constants Programmable power supply Low resolution DAC replacement Sensor calibration

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 AD5241 / AD52421 provide a single-/dual-channel, 256-position, digitally controlled variable resistor (VR) device. These devices perform the same electronic adjustment function as a potentiometer, trimmer, or variable resistor. Each VR offers a completely programmable value of resistance between the A terminal and the wiper, or the B terminal and the wiper. For the AD5242, the fixed A-to-B terminal resistance of 10 kΩ, 100 kΩ, or 1 MΩ has a 1% channel-to-channel matching tolerance. The nominal temperature coefficient of both parts is 30 ppm/°C.Wiper position programming defaults to midscale at system power on. When powered, the VR wiper position is programmed by an I2C-compatible, 2-wire serial data interface. Both parts have two extra programmable logic outputs available that enable users to drive digital loads, logic gates, LED drivers, and analog switches in their system.The AD5241 / AD5242 are available in surface-mount, 14-lead SOIC and 16-lead SOIC packages and, for ultracompact solutions, 14-lead TSSOP and 16-lead TSSOP packages. All parts are guaranteed to operate over the extended temperature range of −40°C to +105°C.APPLICATIONS Multimedia, video, and audio Communications Mechanical potentiometer replacement Instrumentation: gain, offset adjustment Programmable voltage-to-current conversion Line impedance matching

The AD5243 and AD5248 provide a compact 3 mm × 4.9 mmpackaged solution for dual, 256-position adjustment applications.The AD5243 performs the same electronic adjustment functionas a 3-terminal mechanical potentiometer, and the AD5248performs the same adjustment function as a 2-terminal variableresistor. Available in four end-to-end resistance values (2.5 kΩ,10 kΩ, 50 kΩ, and 100 kΩ), these low temperature coefficientdevices are ideal for high accuracy and stability-variableresistance adjustments. The wiper settings are controllablethrough the I2C-compatible digital interface. The AD5248 hasextra package address decode pins, AD0 and AD1, allowingmultiple parts to share the same I2C, 2-wire bus on a PCB. Theresistance between the wiper and either endpoint of the fixedresistor varies linearly with respect to the digital code transferred into the RDAC latch. (The terms digital potentiometer, VR,and RDAC are used interchangeably.)Operating from a 2.7 V to 5.5 V power supply and consumingless than 6 µA allows the AD5243/AD5248 to be used inportable battery-operated applications.For applications that program the AD5243/AD5248 at thefactory, Analog Devices, Inc., offers device programmingsoftware running on Windows® NT/2000/XP operating systems.This software effectively replaces the need for external I2Ccontrollers, which in turn enhances the time to market ofsystems. An AD5243/AD5248 evaluation kit and software areavailable. The kit includes a cable and instruction manual.Applications Systems calibrations Electronics level settings Mechanical trimmers replacement in new designs Permanent factory printed circuit board (PCB) setting Transducer adjustment of pressure, temperature, position, chemical, and optical sensors RF amplifier biasing Gain control and offset adjustment