The ADAU1442 / ADAU1445 / ADAU1446 are enhanced audio processors that allow full flexibility in routing all input and output signals. The SigmaDSP® core features full 28-bit processing (56-bit in double-precision mode), synchronous parameter loading for ensuring filter stability, and 100% code efficiency with the SigmaStudio™ tools. This DSP allows system designers to compensate for the real-world limitations of speakers, amplifiers, and listening environments, resulting in a dramatic improvement of the perceived audio quality through speaker equalization, multiband compression, limiting, and third-party branded algorithms.The flexible audio routing matrix (FARM) allows the user to multiplex inputs from multiple sources running at various sample rates to or from the SigmaDSP core. This drastically reduces the complexity of signal routing and clocking issues in the audio system. FARM includes up to eight stereo asynchronous sample rate converters (depending on the device model), Sony/ Philips Digital Interconnect Format (S/PDIF) input and output, and serial (I2S) and time division multiplexing (TDM) I/Os. Any of these inputs can be routed to the SigmaDSP core or to any of the asynchronous sample rate converters (ASRCs). Similarly, any one of the output signals can be taken from the SigmaDSP core or from any of the ASRC outputs. This routing scheme, which can be modified at any time via control registers, allows for maximum system flexibility.The ADAU1442, ADAU1445, and ADAU1446 differ only in ASRC functionality and packaging. The ADAU1442 / ADAU1445 contain 16 channels of ASRCs and are packaged in TQFP packages, whereas the ADAU1446 contains no ASRCs and is packaged in an LQFP. The ADAU1442 can handle nine clock domains, the ADAU1445 can handle three clock domains, and the ADAU1446 can handle one clock domain.The ADAU1442 / ADAU1445 / ADAU1446 can be controlled in one of two operational modes: the settings of the chip can be loaded and dynamically updated through the SPI/I2C® port, or the DSP can self-boot from an external EEPROM in a system with no microcontroller. There is also a bank of multipurpose (MP) pins that can be used as general-purpose digital I/Os or as inputs to the 4-channel auxiliary control ADC.The ADAU1442 / ADAU1445 / ADAU1446 are supported by the SigmaStudio graphical development environment. This software includes audio processing blocks such as FIR and IIR filters, dynamics processors, mixers, low level DSP functions, and third-party algorithms for fast development of custom signal flows.APPLICATIONS Automotive audio processing Head units Navigation systems Rear-seat entertainment systems DSP amplifiers (sound system amplifiers) Commercial audio processing

The AD5122A/AD5142A potentiometers provide a nonvolatile solution for 128-/256-position adjustment applications, offering guaranteed low resistor tolerance errors of ±8% and up to ±6 mA current density in the Ax, Bx, and Wx pins.The low resistor tolerance and low nominal temperature coefficient simplify open-loop applications as well as applications requiring tolerance matching.The linear gain setting mode allows independent programming of the resistance between the digital potentiometer terminals, through RAW and RWB the string resistors, allowing very accurate resistor matching.The high bandwidth and low total harmonic distortion (THD) ensure optimal performance for ac signals, making it suitable for filter design.The low wiper resistance of only 40 Ω at the ends of the resistor array allows for pin-to-pin connection.The wiper values can be set through an I2C-compatible digital interface that is also used to read back the wiper register and EEPROM contents..The AD5122A/AD5142A are available in a compact, 16-lead, 3 mm × 3 mm LFCSP and a 16-lead TSSOP. The parts are guaranteed to operate over the extended industrial temperature range of −40°C to +125°C.APPLICATIONS Portable electronics level adjustment LCD panel brightness and contrast controls Programmable filters, delays, time constants Programmable power supplies

The AD5700/AD5700-1 are single-chip solutions, designedand specified to operate as a HART® FSK half-duplex modem,complying with the HART physical layer requirements. TheAD5700/AD5700-1 integrate all of the necessary filtering, signaldetection, modulating, demodulating and signal generationfunctions, thus requiring few external components. The 0.5%precision internal oscillator on the AD5700-1 greatly reducesthe board space requirements, making it ideal for line-poweredapplications in both master and slave configurations. The maximumsupply current consumption is 115µA, making theAD5700/AD5700-1 an optimal choice for low power loop-powered applications.Transmit waveforms are phase continuous 1200 Hz and2200 Hz sinusoids. The AD5700/AD5700-1 contain accuratecarrier detect circuitry and use a standard UART interface.Applications Field transmitters HART multiplexers PLC and DCS analog I/O modules HART network connectivity

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 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