RF SWITCHES;

INSTRUMENT AMPLIFIER;

Up-Down Converters hi IP3 Downconverter SMT 1.4 - 2.3 GHz

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

The AD5227 is Analog Devices’ latest 64-step up/down control digital potentiometer. This device performs the same electronic adjustment function as a 5 V potentiometer or variable resistor. Its simple 3-wire up/down interface allows manual switching or high speed digital control. The AD5227 presets to midscale at power-up. When CS is enabled, the devices changes step at every clock pulse. The direction is determined by the state of the U/D pin (see ). The interface is simple to activate by any host controller, discrete logic, or manually with a rotary encoder or pushbuttons. The AD5227’s 64-step resolution, small footprint, and simple interface enable it to replace mechanical potentiometers and trimmers with typically 6× improved resolution, solid-state reliability, and design layout flexibility, resulting in a considerable cost savings in end users’ systems.The AD5227 is available in a compact thin SOT-23-8 (TSOT-8) Pb-free package. The part is guaranteed to operate over the automotive temperature range of −40°C to +105°C.Users who consider EEMEM potentiometers should refer to some recommendations in the Applications section.APPLICATIONS Mechanical potentiometer and trimmer replacements LCD backlight, contrast, and brightness controls Portable electronics level adjustment Programmable power supply Digital trimmer replacements Automatic closed-loop control

The HMC572LC5 is a compact GaAs MMIC I/Q downconverter in a leadless RoHS compliant SMT package. This device provides a small signal conversion gain of 8 dB with a noise figure of 3.5 dB and 18 dB of image rejection across the frequency band. The HMC572LC5 utilizes an LNA followed by an image reject mixer which is driven by an active x2 multiplier.The image reject mixer eliminates the need for a filter following the LNA, and removes thermal noise at the image frequency. I and Q mixer outputs are provided and an external 90° hybrid is needed to select the required sideband. The HMC572LC5 is a much smaller alternative to hybrid style image reject mixer downconverter assemblies, and it eliminates the need for wire bonding by allowing the use of surface mount manufacturing techniques.APPLICATIONS Point-to-Point Point-to-Multi-Point Radio Military Radar, EW & ELINT Satellite Communications

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