Demonstration circuit 559 is a high efficiency synchronous boost DC/DC converter with output disconnect, inrush current limiting and soft-start functions featuring the LTC3429. DC559A-A uses the LTC3429 Burst Mode capable device; DC559A-B uses the continuous switching LTC3429B (Burst Mode disabled). The demo board is capable of supplying 3.3V@90mA from a single AA cell input or 3.3V@250mA from a 2-cell input. The input range is from 1V to 3.3V.

Demonstration circuit 561 is a high current stepdown PolyPhaseTM converter featuring the LTC3731 three-phase synchronous buck controller. The input voltage is from 10V to 14V and output is 1.5V. DC561A-A can provide up to 180A output current with a 12-phase buck circuit, while DC561A-B is a 6-phase buck converter with up to 90A output current. An optional VID controller circuit is available on both DC561A-A and DC561A-B demo circuits for output voltage programming.

The LTC4556 provides all necessary power control, level translation and supervisory functions for a smart card or S.A.M. card interface. The part contains a low noise charge pump plus LDO for generating VCC power, as well as all necessary level shifting circuitry.The card voltage can be set to either 1.8V, 3V or 5V. The LTC4556 includes a card detection channel with automatic debounce circuitry. To reduce wiring costs, the LTC4556 interfaces to a microcontroller via a simple 4?wire serial interface. Multiple devices may be connected in daisy-chain fashion so that the number of wires to the card socket board is independent of the number of sockets. Status data is returned over the same interface.Extensive security features ensure proper deactivation sequencing in the event of a supply fault or a smart card electrical fault. The smart card pins can withstand greater than 10kV ESD in-situ with no additional components. The LTC4556 is available in a small, low profile (0.75mm), 4mm ? 4mm QFN package.Applications Handheld Payment Terminals Pay Telephones ATM Machines POS Terminals Computer Keyboards Multiple S.A.M. Sockets

The LTC2410 is a 2.7V to 5.5V micropower 24-bit differential ?? analog to digital converter with an integrated oscillator, 2ppm INL and 0.16ppm RMS noise. It uses delta-sigma technology and provides single cycle settling time for multiplexed applications. Through a single pin, the LTC2410 can be configured for better than 110dB input differential mode rejection at 50Hz or 60Hz ?2%, or it can be driven by an external oscillator for a user defined rejection frequency. The internal oscillator requires no external frequency setting components.The converter accepts any external differential reference voltage from 0.1V to VCC for flexible ratiometric and remote sensing measurement configurations. The full-scale differential input range is from ?0.5VREF to 0.5VREF. The reference common mode voltage, VREFCM, and the input common mode voltage, VINCM, may be independently set anywhere within the GND to VCC range of the LTC2410. The DC common mode input rejection is better than 140dB.The LTC2410 communicates through a flexible 3-wire digital interface which is compatible with SPI and MICROWIRE protocols.Applications Direct Sensor Digitizer Weight Scales Direct Temperature Measurement Gas Analyzers Strain-Gauge Transducers Instrumentation Data Acquisition Industrial Process Control 6-Digit DVMs

The LT1638 is a low power dual rail-to-rail input and output operational amplifier available in the standard 8-pin PDIP and SO packages as well as the 8-lead MSOP package. The LT1639 is a low power quad rail-to-rail input and output operational amplifier offered in the standard 14-pin PDIP and surface mount packages. For space limited applications the LT1638 is available in a 3mm ? 3mm ? 0.8mm dual fine pitch leadless package (DFN).The LT1638/LT1639 op amps operate on all single and split supplies with a total voltage of 2.5V to 44V drawing only 170?A of quiescent current per amplifier. These amplifiers are reverse battery protected and draw no current for reverse supply up to 18V.The input range of the LT1638/LT1639 includes both supplies, and a unique feature of this device is its capability to operate over the top with either or both of its inputs above V+. The inputs handle 44V, both differential and common mode, independent of supply voltage. The input stage incorporates phase reversal protection to prevent false outputs from occurring when the inputs are below the negative supply. Protective resistors are included in the input leads so that current does not become excessive when the inputs are forced below the negative supply. The LT1638/LT1639 can drive loads up to 25mA and still maintain rail-to-rail capability. The op amps are unity-gain stable and drive all capacitive loads up to 1000pF when optional output compensation is used.Applications Battery- or Solar-Powered Systems Portable Instrumentation Sensor Conditioning Supply Current Sensing Battery Monitoring Micropower Active Filters 4mA to 20mA Transmitters

The LTC1540 is an ultralow power, single comparator with built-in reference. The comparator?s features include less than 0.6?A supply current over the commercial temperature range, a 1.182V ?2% reference, programmable hysteresis and TTL/CMOS outputs that sink and source current. The reference output can drive a bypass capacitor of up to 0.01?F without oscillation.The comparator operates from a single 2V to 11V supply or a dual ?1V to ?5.5V supply. Comparator hysteresis is easily programmed by using two resistors and the HYST pin. Each comparator?s input operates from the negative supply to within 1.3V of the positive supply. The comparator output stage can continuously source up to 40mA. By eliminating the cross-conducting current that normally occur when the comparator changes logic states, power supply glitches are eliminated.The LTC1540 is available in the 8-pin MSOP and SO packages. For space limited applications, the LTC1540 is available in a 3mm ? 3mm low profile (0.8mm) dual fine-pitch leadless package (DFN).Applications Battery-Powered System Monitoring Threshold Detectors Window Comparators Oscillator Circuits

Demonstration circuit 611 is a dual, spread-spectrum, step-down charge pump DC/DC converter featuring the LTC3252EDE. It produces regulated 1.5V and 1.2V output voltages at up to 250mA of output current each, from a 2.7V to 5.5V input. The unique spread spectrum architecture of the LTC3252 provides highly efficient, low noise operation. The circuit has a low external parts count and requires only five small surface mount capacitors and four tiny surface mount resistors.

Demonstration circuit 614 is a monolithic step-down DC/DC switching converter featuring the LT3434. The board is optimized for 3.3V output at up to 2A load current (the LTC3434 is a 3A capable device) for a steady state input voltage range of 4V to about 42V with input transients up to 60V. Minimum on-time restrictions and the 3.3V output may limit the steady state maximum input voltage to 42V before pulse skipping occurs.

DC626A-B: Demo Board for the LTC1569-7 Linear Phase, DC Accurate, Tunable 10th Order Low Pass Filter.

DC629A: Demo Board for the LTC3205 Multi-Display LED Controller.

Demonstration circuit 634 is a low noise avalanche photodiode (APD) bias supply featuring the LT1930A. This circuit takes an input voltage from 3V to 5.5V and provides 90V@2mA at the output (0V control voltage). The output voltage can be adjusted from 90V down to 30V by increasing the control voltage (4.5V max), which effectively changes the current into the feedback node to adjust the output voltage.

DC637A: Demo Board for the LT3465 1.2MHz White LED Step-Up Converters with Built-In Schottky in ThinSOT.

DC642A: Demo Board for the LT5521 Very High Linearity Active Mixer.

The LT5520 mixer is designed to meet the high linearity requirements of wireless and cable infrastructure transmission applications. A high-speed, internally matched, LO amplifier drives a double-balanced mixer core, allowing the use of a low power, single-ended LO source. An RF output transformer is integrated, thus eliminating the need for external matching components at the RF output, while reducing system cost, component count, board area and system-level variations. The IF port can be easily matched to a broad range of frequencies for use in many different applications.The LT5520 mixer delivers 15.9dBm typical input 3rd order intercept point at 1.9GHz with IF input signal levels of ?10dBm. The input 1dB compression point is typically 4dBm. The IC requires only a single 5V supply.Applications Wireless Infrastructure Cable Downlink Infrastructure Point-to-Point Data Communications High Linearity Frequency Conversion

The LTC4057 is a constant-current/constant-voltage linearcharger for single-cell lithium-ion batteries. ItsThinSOT? package and low external component countmake the LTC4057 especially well suited for portableapplications. Furthermore, the LTC4057 is specificallydesigned to work within USB power specifications.No external sense resistor is needed and no blocking diodeis required due to the internal MOSFET architecture.Thermal feedback prevents overheating by regulating thecharge current to limit the die temperature during highpower operation or high ambient temperature conditions.The charge voltage is preset at 4.2V and the charge currentcan be programmed externally with a single resistor.When the input supply (wall adapter or USB supply) isremoved, the LTC4057 automatically enters a low currentstate, dropping the battery drain current to less than 2?A.With power applied, the LTC4057 can be put into shutdownmode, reducing the supply current to 25?A.For the standalone version (on-board charge termination)of the LTC4057, refer to the LTC4054.Applications Wireless PDAs Cellular Phones Portable Electronics

Demonstration circuit 662 is a monolithic step-down DC/DC switching converter featuring the LT1933 in the TSOT-23-6 package. The board is optimized for 3.3V output at up to 500mA load current and requires an input voltage ranging from 4.5V to 36V.

Demonstration circuit 663 is a 2-phase dual synchronous high efficiency step-down DC/DC converter featuring the LTC3736EUF controller. The LTC3736 features Burst Mode operation at light loads. The demo board operates with a 2.7V to 8V input voltage range and provides outputs of 2.5V@5A and 1.8V@5A.

The LTC3737 is a 2-phase dual step-down switching regulator controller that requires few external components. The constant frequency current mode architecture provides excellent AC and DC load and line regulation. MOSFET VDS sensing eliminates the need for current sense resistors and improves efficiency. Power loss and noise due to the ESR of the input capacitance are minimized by operating the two controllers out of phase.Burst Mode operation provides high efficiency operation at light loads. 100% duty cycle provides low dropout operation and extends battery operating time.Switching frequency can be programmed up to 750kHz, allowing the use of small surface mount inductors and capacitors. For noise sensitive applications, the LTC3737 can be externally synchronized from 250kHz to 850kHz.Other features include a power good output voltage monitor, a tracking input and internal soft-start.The LTC3737 is available in the low profile thermally enhanced (4mm ? 4mm) QFN package or a 24-lead SSOP narrow package.Protected by U.S. Patents, including 5481178, 5731694, 5929620, 6144194, 6580258, 5994885Applications One or Two Lithium-Ion Powered Devices Notebook and Palmtop Computers, PDAs Portable Instruments Distributed DC Power Systems

DC665A: Demo Board for the LT4220 Dual Supply Hot Swap Controller.

DC670A: Demo Board for the LT3462 Inverting 1.2MHz/2.7MHz DC/DC Converters with Integrated Schottky in ThinSOT.