The Analog Devices, Inc., amplifier mezzanine card (AMC) analog-to-digital converter (ADC) driver evaluates the performance of amplifiers in 8-lead, single and dual SOIC, 6-lead single SOT23, 8-lead dual MSOP, and 16-lead LFCSP packages. This add on board can be inserted on ADC evaluation boards using its 7-pin header. Figure 1 shows the AMC mounted on an Analog Devices, Inc., ADC evaluation board. The AMC can support any of Analog Devices operational amplifiers and ADC drivers in different packages. The user can configure the ADC driver as a Sallen-Key low-pass, high-pass, or band-pass filter, as a multiple feedback low-pass, high-pass, or band-pass filter, or as an inverting and noninverting operational amplifier. The user can also configure the AMC to drive a single-ended, fully differential, or a single-ended signal to a differential ADC. Optimized power and ground planes ensure low noise and high speed operation. Component placement and power supply bypassing are optimized for maximum circuit flexibility and performance. The AMC evaluation board accepts 0402 or 0603 surface mount technology (SMT) components, 1206 bypass capacitors, and 2.54 mm headers. All components are placed on the primary side. No components are placed on the secondary side.

The LTC4125 is a simple and high performance monolithic full bridge resonant driver capable of delivering over 5W of power wirelessly to a properly tuned receiver. The device controls the current flow in a series connected transmit coil LC network to create a simple, safe and versatile wireless power transmitter.The LTC4125 automatically adjusts its driving frequency to match the LC network resonant frequency. This AutoResonant switching allows the device to deliver maximum power from a low voltage input supply (3V to 5.5V) to a tuned receiver. To optimize system efficiency, the LTC4125 employs a periodic transmit power search and adjusts the transmission power based on the receiver load requirements. The device stops delivering power during a fault condition, or if a foreign object is detected.The LTC4125 also includes a programmable maximum average input current limit and an NTC input as additional means for foreign object and overload protection. The LTC4125 is available in a 20-lead low profile (0.75mm) 4mm ? 5mm QFN package.Applications Hermetically and/or Electrically Insulated Devices Military Sensors and Devices Medical Equipment Industrial Handhelds

The AD5940 and AD5941 are high precision, low power analog front ends (AFEs) designed for portable applications that require high precision, electrochemical-based measurement techniques, such as amperometric, voltammetric, or impedance measurements. The AD5940/AD5941 is designed for skin impedance and body impedance measurements, and works with the AD8233 AFE in a complete bioelectric or biopotential measurement system. The AD5940/AD5941 is designed for electrochemical toxic gas sensing.The AD5940/AD5941 consist of two high precision excitation loops and one common measurement channel, which enables a wide capability of measurements of the sensor under test. The first excitation loop consists of an ultra low power, dual-output string, digital-to-analog converter (DAC), and a low power, low noise potentiostat. One output of the DAC controls the noninverting input of the potentiostat, and the other output controls the noninverting input of the transimpedance amplifier (TIA). This low power excitation loop is capable of generating signals from dc to 200 Hz.The second excitation loop consists of a 12-bit DAC, referred to as the high speed DAC. This DAC is capable of generating high frequency excitation signals up to 200 kHz.The AD5940/AD5941 measurement channel features a 16-bit, 800 kSPS, multichannel successive approximation register (SAR) analog-to-digital converter (ADC) with input buffers, a built in antialias filter, and a programmable gain amplifier (PGA). An input multiplexer (mux) in front of the ADC allows the user to select an input channel for measurement. These input channels include multiple external current inputs, external voltage inputs, and internal channels. The internal channels allow diagnostic measurements of the internal supply voltages, die temperature, and reference voltages.The current inputs include two TIAs with programmable gain and load resistors for measuring different sensor types. The first TIA, referred to as the low power TIA, measures low bandwidth signals. The second TIA, referred to as the high speed TIA, measures high bandwidth signals up to 200 kHz.An ultra low leakage, programmable switch matrix connects the sensor to the internal analog excitation and measurement blocks. This matrix provides an interface for connecting external transimpedance amplifier resistors (RTIAs) and calibration resistors. The matrix can also be used to multiplex multiple electronic measurement devices to the same wearable electrodes.A precision 1.82 V and 2.5 V on-chip reference source is available. The internal ADC and DAC circuits use this on-chip reference source to ensure low drift performance for the 1.82 V and 2.5 V peripherals.The AD5940/AD5941 measurement blocks can be controlled via direct register writes through the serial peripheral interface (SPI) interface, or, alternatively, by using a preprogrammable sequencer, which provides autonomous control of the AFE chip. 6 kB of static random access memory (SRAM) is partitioned for a deep data first in, first out (FIFO) and command FIFO. Measurement commands are stored in the command FIFO and measurement results are stored in the data FIFO. A number of FIFO related interrupts are available to indicate when the FIFO is full.A number of general-purpose inputs/outputs (GPIOs) are available and controlled using the AFE sequencer. The AFE sequencer allows cycle accurate control of multiple external sensor devices.The AD5940/AD5941 operate from a 2.8 V to 3.6 V supply and are specified over a temperature range of ?40?C to +85?C. The AD5940 is packaged in a 56-lead, 3.6 mm ? 4.2 mm WLCSP. The AD5941 is packaged in a 48-lead LFCSP.APPLICATIONS Electrochemical measurements Electrochemical gas sensors Potentiostat/amperometric/voltammetry/cyclic voltammetry Bioimpedance applications Skin impedance Body impedance Continuous glucose monitoring Battery impedance

The LTC1503-1.8/LTC1503-2 are switched capacitor step-down DC/DC converters that produce a regulated output from a 2.4V to 6V input. The parts use switched capacitor fractional conversion to achieve high efficiency over the entire input range. No inductors are required. Internal circuitry controls the step-down conversion ratio to optimize efficiency as the input voltage and load conditions vary. Typical efficiency is 25% higher than that of a low dropout (LDO) linear regulator.Regulation is achieved by sensing the output voltage and enabling the internal switching network as needed to maintain a fixed output voltage. This method of regulation enables the parts to achieve high efficiency at extremely light loads. Low operating current (25?A with no load, 5?A in shutdown) and low external parts count (two 1?F flying capacitors and two 10?F bypass capacitors) make the LTC1503-1.8/LTC1503-2 ideally suited for space constrained battery-powered applications. The parts are fully short-circuit and over temperature protected.The LTC1503-1.8/LTC1503-2 are available in 8-pin MSOP and SO packages.Applications Cellular Phones Handheld Computers Smart Card Readers Low Power DSP Supplies Portable Electronic Equipment Handheld Medical Instruments

The LTC4066/LTC4066-1 are USB power managers and Li-Ion battery chargers designed to work in portable battery-powered applications. The parts control the total current used by the USB peripheral for operation and battery charging. The total input current can be limited to 100mA, 500mA or ?unlimited? (i.e., above 2A). Battery charge current is automatically reduced such that the sum of the load current and the charge current does not exceed the programmed input current limit.The LTC4066/LTC4066-1 include a standalone constant-current / constant-voltage linear charger for single cell Li-ion batteries. The ?oat voltage applied to the battery is held to a tight 0.8% tolerance, and charge current is programmable using an external resistor to ground. A programmable end-of-charge status output (CHRG) indicates full charge. BAT pin charge and discharge currents can be monitored via an analog output (ISTAT). Total charge time is programmable by an external capacitor to ground. When the battery drops 100mV below the ?oat voltage, automatic recharging of the battery occurs. Also featured is an NTC thermistor input used to monitor battery temperature while charging.The LTC4066/LTC4066-1 are available in a 24-pin thin pro?le (0.75mm) 4mm x 4mm QFN package. The LTC4066 is also available in a 24-pin ultrathin pro?le (0.55mm) 4mm x 4mm UTQFN package.Applications Portable USB Devices GPS, Cameras, Broadband Wireless Modems Mulitple Input Chargers

The ADF4360-8 is an integrated integer-N synthesizer and voltagecontrolled oscillator (VCO). The ADF4360-8 center frequencyis set by external inductors. This allows a frequencyrange of between 65 MHz to 400 MHz. Control of all the on-chip registers is through a simple 3-wire interface. The device operates with a power supply ranging from 3.0 V to 3.6 V and can be powered down when not in use.?

The HMC639ST89(E) is a GaAs PHEMT, High Linearity, Low Noise, Wideband Gain Block Amplifier covering 0.2 to 4.0 GHz. Packaged in an industry standard SOT89, the amplifier can be used as either a cascadable 50 Ohm gain stage, a PA Pre-Driver, a Low Noise Amplifier, or a Gain Block with up to +22 dBm output power. This versatile Gain Block Amplifier is powered from a single +5V supply and requires no external matching components. The internally matched topology permits this amplifier to be readily ported between virtually any printed circuit board material, regardless of its dielectric constant, thickness, or composition.Applications Cellular / PCS / 3G WiMAX, WiBro, & Fixed Wireless CATV & Cable Modem Microwave Radio IF and RF Sections?

Demonstration circuit 2176A features the LT3909, a 2-string × 50mA, 2MHz step-up LED driver with ±1.8% current matching. The LT3909 precisely regulates two LED strings for equal current, supports LED dimming that reduces brightness down to a 1/40,000 ratio, protects against faults and also reports faults. The LT3909 consists of a step-up converter with a fixed 2MHz switching frequency and current sources for the LED strings. The maximum current in each LED string is 40mA. The ISET resistor can be changed to 20.0kΩ to program the string current to 50mA – see the data sheet for an application example with 50mA string current. Voltage feedback resistors optimize operation for LEDs that are 35V maximum.

DC1851A: Demo Board for the LTC2872 RS232/RS485 Dual Multiprotocol Transceiver with Integrated Termination.

The ADXL362 is an ultralow power, 3-axis MEMS accelerometer that consumes less than 2 ?A at a 100 Hz output data rate and 270 nA when in motion triggered wake-up mode. Unlike accelerometers that use power duty cycling to achieve low power consumption, the ADXL362 does not alias input signals by undersampling; it samples the full bandwidth of the sensor at all data rates.The ADXL362 always provides 12-bit output resolution; 8-bit formatted data is also provided for more efficient single-byte transfers when a lower resolution is sufficient. Measurement ranges of ?2 g, ?4 g, and ?8 g are available, with a resolution of 1 mg/LSB on the ?2 g range. For applications where a noise level lower than the normal 550 ?g/?Hz of the ADXL362 is desired, either of two lower noise modes (down to 175 ?g/?Hz typical) can be selected at minimal increase in supply current.In addition to its ultralow power consumption, the ADXL362 has many features to enable true system level power reduction. It includes a deep multimode output FIFO, a built-in micropower temperature sensor, and several activity detection modes including adjustable threshold sleep and wake-up operation that can run as low as 270 nA at a 6 Hz (approximate) measurement rate. A pin output is provided to directly control an external switch when activity is detected, if desired. In addition, the ADXL362 has provisions for external control of sampling time and/or an external clock.The ADXL362 operates on a wide 1.6 V to 3.5 V supply range, and can interface, if necessary, to a host operating on a separate, lower supply voltage. The ADXL362 is available in a 3 mm ? 3.25 mm ? 1.06 mm package.APPLICATIONS Hearing aids Home healthcare devices Motion enabled power save switches Wireless sensors Motion enabled metering devices