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 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 AD590 is a 2-terminal integrated circuit temperature trans-ducer that produces an output current proportional to absolute temperature. For supply voltages between 4 V and 30 V, the device acts as a high impedance, constant current regulator passing 1 μA/K. Laser trimming of the chip’s thin-film resistors is used to calibrate the device to 298.2 μA output at 298.2 K (25°C).The AD590 should be used in any temperature-sensing application below 150°C in which conventional electrical temperature sensors are currently employed. The inherent low cost of a monolithic integrated circuit combined with the elimination of support circuitry makes the AD590 an attractive alternative for many temperature measurement situations. Linearization circuitry, precision voltage amplifiers, resistance measuring circuitry, and cold junction compensation are not needed in applying the AD590.In addition to temperature measurement, applications include temperature compensation or correction of discrete components, biasing proportional to absolute temperature, flow rate measurement, level detection of fluids and anemometry. The AD590 is available in die form, making it suitable for hybrid circuits and fast temperature measurements in protected environments.The AD590 is particularly useful in remote sensing applications. The device is insensitive to voltage drops over long lines due to its high impedance current output. Any well-insulated twisted pair is sufficient for operation at hundreds of feet from the receiving circuitry. The output characteristics also make the AD590 easy to multiplex: the current can be switched by a CMOS multiplexer, or the supply voltage can be switched by a logic gate output.PRODUCT HIGHLIGHTS The AD590 is a calibrated, 2-terminal temperature sensor requiring only a dc voltage supply (4 V to 30 V). Costly transmitters, filters, lead wire compensation, and linearization circuits are all unnecessary in applying the device. State-of-the-art laser trimming at the wafer level in conjunction with extensive final testing ensures that AD590 units are easily interchangeable. Superior interface rejection occurs because the output is a current rather than a voltage. In addition, power requirements are low (1.5 mW @ 5 V @ 25°C). These features make the AD590 easy to apply as a remote sensor. The high output impedance (>10 MΩ) provides excellent rejection of supply voltage drift. For instance, changing the power supply from 5 V to 10 V results in only a 1 μA maximum current change, or 1°C equivalent error. The AD590 is electrically durable: it withstands a forward voltage of up to 44 V and a reverse voltage of 20 V. Therefore, supply irregularities or pin reversal does not damage the device.

The AD590 is a 2-terminal integrated circuit temperature trans-ducer that produces an output current proportional to absolute temperature. For supply voltages between 4 V and 30 V, the device acts as a high impedance, constant current regulator passing 1 μA/K. Laser trimming of the chip’s thin-film resistors is used to calibrate the device to 298.2 μA output at 298.2 K (25°C).The AD590 should be used in any temperature-sensing application below 150°C in which conventional electrical temperature sensors are currently employed. The inherent low cost of a monolithic integrated circuit combined with the elimination of support circuitry makes the AD590 an attractive alternative for many temperature measurement situations. Linearization circuitry, precision voltage amplifiers, resistance measuring circuitry, and cold junction compensation are not needed in applying the AD590.In addition to temperature measurement, applications include temperature compensation or correction of discrete components, biasing proportional to absolute temperature, flow rate measurement, level detection of fluids and anemometry. The AD590 is available in die form, making it suitable for hybrid circuits and fast temperature measurements in protected environments.The AD590 is particularly useful in remote sensing applications. The device is insensitive to voltage drops over long lines due to its high impedance current output. Any well-insulated twisted pair is sufficient for operation at hundreds of feet from the receiving circuitry. The output characteristics also make the AD590 easy to multiplex: the current can be switched by a CMOS multiplexer, or the supply voltage can be switched by a logic gate output.PRODUCT HIGHLIGHTS The AD590 is a calibrated, 2-terminal temperature sensor requiring only a dc voltage supply (4 V to 30 V). Costly transmitters, filters, lead wire compensation, and linearization circuits are all unnecessary in applying the device. State-of-the-art laser trimming at the wafer level in conjunction with extensive final testing ensures that AD590 units are easily interchangeable. Superior interface rejection occurs because the output is a current rather than a voltage. In addition, power requirements are low (1.5 mW @ 5 V @ 25°C). These features make the AD590 easy to apply as a remote sensor. The high output impedance (>10 MΩ) provides excellent rejection of supply voltage drift. For instance, changing the power supply from 5 V to 10 V results in only a 1 μA maximum current change, or 1°C equivalent error. The AD590 is electrically durable: it withstands a forward voltage of up to 44 V and a reverse voltage of 20 V. Therefore, supply irregularities or pin reversal does not damage the device.

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 ADuM1100 is a digital isolator based on Analog Devices Inc., iCoupler® technology. Combining high speed CMOS and monolithic air core transformer technology, this isolation component provides outstanding performance characteristics superior to alternatives, such as optocoupler devices.Configured as a pin-compatible replacement for existing high speed optocouplers, the ADuM1100 supports data rates as high as 25 Mbps and 100 Mbps.The ADuM1100 operates with a voltage supply ranging from 3.0 V to 5.5 V, boasts a propagation delay of <18 ns and edge asymmetry of <2 ns, and is compatible with temperatures up to 125°C. It operates at very low power, less than 0.9 mA of quiescent current (sum of both sides), and a dynamic current of less than 160 μA per Mbps of data rate. Unlike other optocoupler alternatives, the ADuM1100 provides dc correctness with a patented refresh feature that continuously updates the output signal.The ADuM1100 is offered in three grades. The ADuM1100AR and ADuM1100BR can operate up to a maximum temperature of 105°C and support data rates up to 25 Mbps and 100 Mbps, respectively. The ADuM1100UR can operate up to a maximum temperature of 125°C and supports data rates up to 100 Mbps.APPLICATIONS Digital field bus isolation Opto-isolator replacement Computer-peripheral interface Microprocessor system interface General instrumentation and data acquisition applications

The ADuM2400/ADuM2401/ADuM2402 are 4-channel digital isolators based on Analog Devices, Inc., iCoupler® technology. Combining high speed CMOS and monolithic air core transformer technology, these isolation components provide outstanding performance characteristics that are superior to alternatives, such as optocoupler devices. By avoiding the use of LEDs and photodiodes, iCoupler devices remove the design difficulties commonly associated with opto-couplers. The typical optocoupler concerns regarding uncertain current transfer ratios, nonlinear transfer functions, and temperature and lifetime effects are eliminated with the simple iCoupler digital interfaces and stable performance characteristics. Furthermore, iCoupler devices run at one-tenth to one-sixth the power of optocouplers at comparable signal data rates.The ADuM2400/ADuM2401/ADuM2402 isolators provide four independent isolation channels in a variety of channel configurations and data rates (see the Ordering Guide). The ADuM2400/ADuM2401/ADuM2402 models operate with the supply voltage of either side ranging from 2.7 V to 5.5 V, providing compatibility with lower voltage systems as well as enabling a voltage translation functionality across the isolation barrier. In addition, the ADuM2400/ADuM2401/ADuM2402 provide low pulse width distortion (<2 ns for CRWZ grade) and tight channel-to-channel matching (<2 ns for CRWZ grade). The ADuM2400/ADuM2401/ADuM2402 isolators have a patented refresh feature that ensures dc correctness in the absence of input logic transitions and during power-up/power-down conditions.APPLICATIONS General-purpose, high voltage, multichannel isolation Medical equipment Motor drives Power supplies

The AD5280/AD5282 are single-channel and dual-channel, 256-position, digitally controlled variable resistors (VRs)2. The 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. The fixed A-to-B terminal resistance of 20 kΩ, 50 kΩ, or 200 kΩ has a 1% channel-to-channel matching tolerance. The nominal temperature coefficient of both parts is 30 parts per million/ degrees centigrade (ppm/°C). Another key feature is that the parts can operate up to +15 V or ±5 V.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. The AD5280/ AD5282 feature sleep mode programmability. This allows any level of preset in power-up and is an alternative to a costly EEPROM solution. Both parts have additional programmable logic outputs that enable users to drive digital loads, logic gates, LED drivers, and analog switches in their system.The AD5280/AD5282 are available in thin, surface-mounted 14-lead TSSOP and 16-lead TSSOP. All parts are guaranteed to operate over the extended industrial temperature range of −40°C to +85°C. For 3-wire SPI-compatible interface applica-tions, see the AD5260/AD5262 product information on www.analog.com.Applications Multimedia, video, and audio Communications Mechanical potentiometer replacement Instrumentation: gain, offset adjustment Programmable voltage source Programmable current source Line impedance matching1 Assert shutdown and program the device during power-up, then deassert the shutdown to achieve the desired preset level.2 The terms digital potentiometer, VR, and RDAC are used interchangeably.

The AD22057 is a single-supply difference amplifier for the amplification and low-pass filtering of small differential voltages from sources having a large common-mode voltage.Supply voltages from +3 V to +36 V can be used. The input common-mode range extends from below ground to 24 V using a +5 V supply with excellent rejection of this common-mode voltage.This range is achieved by the use of a special resitive attenuator at the input, laser trimmed to a very high differential balance. Low initial offset voltage and offset voltage drift are specified, and long-term stability of gain and offset voltage is also provided.Provisions are included for optional low-pass filtering and gain adjustment. An accurate midscale offset feature allows bipolar signals to be amplified.