The LTC3406 is a high efficiency monolithic synchronous buck regulator using a constant frequency, current mode architecture. The device is available in an adjustable version and fixed output voltages of 1.5V and 1.8V. Supply current during operation is only 20?A and drops to

DC503A: Demo Board for the LT5512 1kHz-3GHz High Signal Level Active Mixer.

The LTC3251/LTC3251-1.2/LTC3251-1.5 are 2-phase charge pump step-down DC/DC converters that produce a regulated output from a 2.7V to 5.5V input. The parts use switched capacitor fractional conversion to achieve twice the typical efficiency of a linear regulator. No inductors are required. VOUT is resistor programmable from 0.9V to 1.6V or fixed at 1.2V or 1.5V, with up to 500mA of load current available.A unique 2-phase spread spectrum architecture provides a very low noise regulated output as well as low noise at the input. The parts have four operating modes: Continuous Spread Spectrum, Spread Spectrum with Burst Mode operation, Super Burst? mode operation and shutdown.Low operating current (35?A in Burst Mode operation, 10?A in Super Burst mode operation) and low external parts count make the LTC3251/LTC3251-1.2/LTC3251-1.5 ideally suited for space-constrained battery-powered applications. The parts are short-circuit and over-temperature protected, and are available in a thermally enhanced 10-pin MSOP package.Applications Handheld Devices Cellular Phones Portable Electronic Equipment DSP Power Supplies

The LTC3729 is a multiple phase, synchronous step-down current mode switching regulator controller that drives N-channel external power MOSFET stages in a phase-lockable fixed frequency architecture. The PolyPhase controller drives its two output stages out of phase at frequencies up to 550kHz to minimize the RMS ripple currents in both input and output capacitors. The output clock signal allows expansion for up to 12 evenly phased controllers for systems requiring 15A to 200A of output current. The multiple phase technique effectively multiplies the fundamental frequency by the number of channels used, improving transient response while operating each channel at an optimum frequency for efficiency. Thermal design is also simplified.An internal differential amplifier provides true remote sensing of the regulated supply?s positive and negative output terminals as required for high current applications.A RUN/SS pin provides both soft-start and optional timed, short-circuit shutdown. Current foldback limits MOSFET dissipation during short-circuit conditions when the overcurrent latchoff is disabled. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3729 includes a power good output pin that indicates when the output is within ?7.5% of the designed set point. Vin Max Vref LTC3729 36V 0.8 LTC3729L-6 30V 0.6 Applications Desktop Computers Large Memory Arrays DC Power Distribution Systems

The LTC2846 is a 3-driver/3-receiver multiprotocol transceiver with on-chip cable termination. When combined with the LTC2844 or LTC2845, this chip set forms a complete software-selectable DTE or DCE interface port that supports the RS232, RS449, EIA530, EIA530-A, V.35, V.36 and X.21 protocols. All necessary cable termination is provided inside the LTC2846. The LTC2846 has a boost regulator that takes in a 3.3V input and switches at 1.2MHz, allowing the use of tiny, low cost capacitors and inductors 2mm or less in height.The 5V output drives an internal charge pump that requires only five space-saving surface mounted capacitors. The LTC2846 is available in a 36-lead SSOP surface mount package.Applications Data Networking CSU and DSU Data Routers

DC539A: Demo Board for the LTC5508 300MHz to 7GHz RF Power Detector with Buffered Output in SC70 Package.

Demonstration circuit 541A is an isolated synchronous push-pull converter featuring the LTC3723-1, LTC3901, LT1431 and LT3710. The design provides an isolated 3.3V at 40A and 2.5V at 10A from a 48V telecom (36V to 72V) input voltage. Isolation voltage is 1500VDC. The demo board also can provide 3.3V @ 50A with the 2.5V output disabled.

The LT1934 is a micropower step-down DC/DC converter with internal 400mA power switch, packaged in a low profile (1mm) ThinSOT. With its wide input range of 3.2V to 34V, the LT1934 can regulate a wide variety of power sources, from 4-cell alkaline batteries and 5V logic rails to unregulated wall transformers and lead-acid batteries. Quiescent current is just 12?A and a zero current shutdown mode disconnects the load from the input source, simplifying power management in battery-powered systems. Burst Mode? operation and the low drop internal power switch result in high efficiency over a broad range of load current.The LT1934 provides up to 300mA of output current. The LT1934-1 has a lower current limit, allowing optimum choice of external components when the required output current is less than 60mA. Fast current limiting protects the LT1934 and external components against shorted outputs, even at 34V input.Applications Wall Transformer Regulation Automotive Battery Regulation Standby Power for Portable Products Distributed Supply Regulation Industrial Control Supplies

Demonstration circuit 545 features the LT3460, step-up DC/DC converter with 1.3MHz constant frequency in a SC70 package. There are two switching regulator circuits in DC545. The 12V output boost converter (upper circuit) is designed to convert 5V input to 12V output at 70mA of load current and the SEPIC converter (lower circuit) is designed to convert 10V ~ 16V input to 12V at 50mA.

DC563A: Demo Board for the LTC2920 Single (-1) & Dual (-2) Margining Controller.

Demonstration Circuit 565 is a constant-frequency synchronous boost converter using the LTC3421. Guaranteed to start-up at 1V input voltage, this converter provides up to 95% efficiency. For 1.8V minimum input voltage, this converter can provide up to 1A load current. This converter has true output disconnect by eliminating body diode conduction of the internal PMOS rectifier. The output voltage is set at 3.3V. A different output voltage in the range of 2.4V to 5.25V can be obtained by changing one of the feedback resistors.

The LTC4053 is a standalone linear charger for lithium-ion batteries that can be powered directly from a USB port. The IC contains an on-chip power MOSFET and eliminates the need for an external sense resistor and blocking diode. Thermal regulation automatically adjusts charge current to limit die temperature during high power or high ambient temperature conditions. This feature protects the end product and the LTC4053 from thermal stress while the IC charges the battery at maximum rate without interruption.The charge current and charge time can be set externally with a single resistor and capacitor, respectively. When the input supply (wall adapter or USB supply) is removed, the LTC4053 automatically enters a low current sleep mode, dropping the battery drain current to less than 5?A.The LTC4053 also includes NTC temperature sensing, C/10 detection circuitry, AC present logic, low battery charge conditioning (trickle charging) and shutdown (25?A supply current).The LTC4053 is available in a 10-pin thermally enhanced MSOP package.Applications Cellular Telephones Handheld Computers Charging Docks and Cradles MP3 Players Digital Cameras

The LT3461/LT3461A are general purpose fixed frequency current mode step-up DC/DC converters. Both devices feature an integrated Schottky and a low VCESAT switch allowing a small converter footprint and lower parts cost. The LT3461 switches at 1.3MHz while the LT3461A switches at 3MHz. These high switching frequencies enable the use of tiny, low cost and low height capacitors and inductors. The constant switching frequency results in predictable output noise that is easy to filter, and the inductor based topology ensures an input free from switching noise typically present with charge pump solutions. The high voltage switch in the LT3461/LT3461A is rated at 40V making the device ideal for boost converters up to 38V.The LT3461/LT3461A are available in a low profile (1mm) SOT-23 package. Switching Frequency LT3461 1.3MHz LT3461A 3MHz Applications Digital Cameras CCD Bias Supply XDSL Power Supply TFT-LCD Bias Supply Local 5V or 12V Supply Medical Diagnostic Equipment Battery Backup

The LT3461/LT3461A are general purpose fixed frequency current mode step-up DC/DC converters. Both devices feature an integrated Schottky and a low VCESAT switch allowing a small converter footprint and lower parts cost. The LT3461 switches at 1.3MHz while the LT3461A switches at 3MHz. These high switching frequencies enable the use of tiny, low cost and low height capacitors and inductors. The constant switching frequency results in predictable output noise that is easy to filter, and the inductor based topology ensures an input free from switching noise typically present with charge pump solutions. The high voltage switch in the LT3461/LT3461A is rated at 40V making the device ideal for boost converters up to 38V.The LT3461/LT3461A are available in a low profile (1mm) SOT-23 package. Switching Frequency LT3461 1.3MHz LT3461A 3MHz Applications Digital Cameras CCD Bias Supply XDSL Power Supply TFT-LCD Bias Supply Local 5V or 12V Supply Medical Diagnostic Equipment Battery Backup

The LT1725 is a monolithic switching regulator controller specifically designed for the isolated flyback topology. It drives the gate of an external MOSFET and is generally powered from a third transformer winding. These features allow for an application input voltage limited only by external power path components. The third transformer winding also provides output voltage feedback information, such that an optoisolator is not required. Its gate drive capability coupled with a suitable external MOSFET can deliver load power up to tens of watts.The LT1725 has a number of features not found on most other switching regulator ICs. By utilizing current mode switching techniques, it provides excellent AC and DC line regulation. Its unique control circuitry can maintain regulation well into discontinuous mode in most applications. Optional load compensation circuitry allows for improved load regulation. An optional undervoltage lockout pin halts operation when the application input voltage is too low. An optional external capacitor implements a soft-start function. A 3V output is available at up to several mA for powering primary side application circuitry.Applications Telecom Isolated Converters Offline Isolated Power Supplies Instrumentation Power Supplies

The LT5522 active downconverting mixer is optimized for high linearity downconverter applications including cable and wireless infrastructure. The IC includes a high speed differential LO buffer amplifier driving a double-balanced mixer. The LO buffer is internally matched for wideband, single-ended operation with no external components.The RF input port incorporates an integrated RF transformer and is internally matched over the 1.2GHz to 2.3GHz frequency range with no external components. The RF input match can be shifted down to 600MHz, or up to 2.7GHz, with a single shunt capacitor or inductor, respectively. The high level of integration minimizes the total solution cost, board space and system-level variation.The LT5522 delivers high performance and small size without excessive power consumption.*Operation over a wider frequency range is possible with reduced performance. Consult factory for information and assistance.Applications Cellular, PCS and UMTS Band Infrastructure CATV Downlink Infrastructure 2.4GHz ISM High Linearity Downmixer Applications

Demonstration circuit 653A is a dual 15A step-down DC/DC converter featuring the LTC3802EGN. The LTC3802EGN itself is a synchronous voltage mode controller. Output #1 of demonstration circuit 653A is a 3.3V / 15A rail and output #2 is a 2.5V / 15A rail. The input voltage range is 7V to 24V.The nominal switching frequency of the LTC3802 is 550kHz and its phase lockable synchronization range is 330kHz to 750kHz.

The AD7719 is a complete analog front-end for low frequency measurement applications. It contains two high-resolution sigma delta ADCs, switchable matched excitation current sources, low-side power switches, digital I/O port and temperature sensor. The 24-bit mainchannel with PGA accepts fully differential, unipolar and bipolar input signal ranges from REFIN1/128 to REFIN1. Signals can be converted directly from a transducer without the need for signal conditioning. The 16-bit aux channel does not have a PGA and has an input signal range of REFIN2 or REFIN2/2.

The AD7730 is a complete analog front end for weigh-scale and pressure measurement applications. The device accepts low-level signals directly from a transducer and outputs a serial digital word. The input signal is applied to a proprietary programmable gain front end based around an analog modulator.The modulator output is processed by a low pass programmable digital filter, allowing adjustment of filter cutoff, output rate and settling time.The part features two buffered differential programmable gain analog inputs as well as a differential reference input. The part operates from a single +5 V supply. It accepts four unipolar analog input ranges: 0 mV to ?10 mV, +20 mV, +40 mV and +80 mV and four bipolar ranges: ?10 mV, ?20 mV, ?40 mV and ?80 mV. The peak-to-peak resolution achievable directly from the part is 1 in 230,000 counts. An on-chip 6-bit DAC allows the removal of TARE voltages. Clock signals for synchronizing ac excitation of the bridge are also provided.The serial interface on the part can be configured for three-wire operation and is compatible with microcontrollers and digital signal processors. The AD7730 contains self-calibration and system calibration options, and features an offset drift of less than 5 nV/?C and a gain drift of less than 2 ppm/?C.The part is available in a 24-pin plastic DIP, a 24-lead SOIC and 24-lead TSSOP package.APPLICATIONS Weigh Scales Pressure Measurement

The AD7761 is an 8-channel, simultaneous sampling sigma-delta (?-?) analog-to-digital converter (ADC) with a ?-? modulator and digital filter per channel, enabling synchronized sampling of ac and dc signals.The AD7761 achieves 97.7 dB dynamic range at a maximum input bandwidth of 110.8 kHz, combined with typical performance of ?1 LSB integral nonlinearity (INL), ?1 LSB offset error, and ?5 LSB gain error.The AD7761 user can trade off input bandwidth, output data rate, and power dissipation. Select one of three power modes to optimize the device for noise targets and power consumption. The flexibility of the AD7761 allows it to become a reusable platform for low power dc and high performance ac measurement modules.The AD7761 has three modes: fast mode (256 kSPS maximum, 110.8 kHz input bandwidth, 51.5 mW per channel), median mode (128 kSPS maximum, 55.4 kHz input bandwidth, 27.5 mW per channel) and low power mode (32 kSPS maximum, 13.8 kHz input bandwidth, 9.375 mW per channel).The AD7761 offers extensive digital filtering capabilities, such as a wideband, low ?0.005 dB pass-band ripple, antialiasing low-pass filter with sharp roll-off, and 105 dB attenuation at the Nyquist frequency.Frequency domain measurements can use the wideband linear phase filter. This filter has a flat pass band (?0.005 dB ripple) from dc to 102.4 kHz at 256 kSPS, from dc to 51.2 kHz at 128 kSPS, or from dc to 12.8 kHz at 32 kSPS.The AD7761 also offers sinc response via a sinc5 filter, a low latency path for low bandwidth, and low noise measurements.The wideband and sinc5 filters can be selected and run on a per channel basis.Within these filter options, the user can improve the dynamic range by selecting from decimation rates of ?32, ?64, ?128, ?256, ?512, and ?1024. The ability to vary the decimation filtering optimizes noise performance to the required input bandwidth.Embedded analog functionality on each ADC channel makes design easier, such as a precharge buffer on each analog input that reduces analog input current and a precharge reference buffer per channel reduces input current and glitches on the reference input terminals.The device operates with a 5 V AVDD1A and AVDD1B supply, a 2.25 V to 5.0 V AVDD2A and AVDD2B supply, and a 2.5 V to 3.3 V or 1.8 V IOVDD supply (see the 1.8 V IOVDD Operation section for specific requirements for operating at 1.8 V IOVDD).The device requires an external reference; the absolute input reference voltage range is 1 V to AVDD1 ? AVSS.For the purposes of clarity within this data sheet, the AVDD1A and AVDD1B supplies are referred to as AVDD1 and the AVDD2A and AVDD2B supplies are referred to as AVDD2. For the negative supplies, AVSS refers to the AVSS1A, AVSS1B, AVSS2A, AVSS2B, and AVSS pins.The specified operating temperature range is ?40?C to +105?C. The device is housed in a 10 mm ? 10 mm 64-lead LQFP package with a 12 mm ? 12 mm printed circuit board (PCB) footprint.Throughout this data sheet, multifunction pins, such as XTAL2/MCLK, are referred to either by the entire pin name or by a single function of the pin, for example MCLK, when only that function is relevant.Applications Data acquisition systems: USB/PXI/Ethernet Instrumentation and industrial control loops Audio testing and measurement Vibration and asset condition monitoring 3-phase power quality analysis Sonar High precision medical electroencephalogram (EEG)/ electromyography (EMG)/electrocardiogram (ECG)