The LTC1730 is a complete pulse charger for 1-cell lithium-ion batteries. When charging a depleted cell, the internal MOSFET is fully on allowing the current limited input power source to provide charge current to the battery, virtually eliminating heat generation in the charger.As the battery accepts charge and approaches the programmed voltage, the internal MOSFET begins switching off and on with the duty cycle gradually decreasing as the battery approaches a fully charged condition. A programmable timer ends the charge cycle. The end-of-charge condition is indicated at the CHRG pin when the average charge current falls to C/10. Removing the input voltage puts the LTC1730 into a sleep mode, dropping the battery current drain to less than 1?A (maximum).An external sense resistor limits the maximum charge current as a safety precaution against a user connecting a wall adapter with the incorrect or no current limit. The internal MOSFET prevents reverse battery current from flowing if the input voltage is shorted to ground, eliminating the need for a blocking diode.The LTC1730-4 is available in the 16-pin SSOP package and the LTC1730-4.2 is available in the 8-pin SO package.Applications Standalone Lithium-Ion Battery Charger Handheld Computers Cellular Telephones

The LTC1923 is a pulse width modulator intended for thermoelectric cooler (TEC) or heater applications requiring either unidirectional or bidirectional drive circuits. All of the necessary control circuitry and two sets of complementary output drivers are integrated into the LTC1923 to drive a full bridge, providing an efficient means of bidirectional current flow to the TEC. An accurate temperature control loop to stabilize the temperature of a laser diode system is easily achieved with the addition of just a few external components. Typical temperature setpoint accuracy of 0.1?C is achievable with the LTC1923. Adding an instrumentation amplifier front end allows setpoint stability of 0.01?C.The part features independent adjustable heating and cooling pulse-by-pulse current limit, current soft-start for controlled start-up, output slew rate control to reduce system noise, differential current sense and voltage amplifiers and a host of auxiliary circuits to protect the laser and provide redundant system monitoring.Applications Laser-Based Fiber Optic Links Medical Instruments CPU Temperature Regulators

The LT1961 is a 1.25MHz monolithic boost switching regulator. A high efficiency 1.5A, 0.2? switch is included on the die together with all the control circuitry required to complete a high frequency, current-mode switching regulator. Current-mode control provides fast transient response and excellent loop stability.New design techniques achieve high efficiency at high switching frequencies over a wide operating voltage range. A low dropout internal regulator maintains consistent performance over a wide range of inputs from 24V systems to Li-Ion batteries. An operating supply current of 1mA maintains high efficiency, especially at lower output currents. Shutdown reduces quiescent current to 6?A. Maximum switch current remains constant at all duty cycles. Synchronization allows an external logic level signal to increase the internal oscillator from 1.5MHz to 2MHz.The LT1961 is available in an exposed pad, 8-pin MSOP package. Full cycle-by-cycle switch current limit protection and thermal shutdown are provided. High frequency operation allows the reduction of input and output filtering components and permits the use of chip inductors.Applications DSL Modems Portable Computers Battery-Powered Systems Distributed Power

DC442A: Demo Board for the LT1950 Single Switch PWM Controller with Auxiliary Boost Converter.

DC459A Demo Board for: LT1946 1.2MHz Boost DC/DC Converter with 1.5A Switch and Soft-Start LT1946A 2.7MHz Boost DC/DC Converter with 1.5A Switch and Soft-Start

DC463A: Demo Board for LTC3700 Constant Frequency Step-Down DC/DC Controller with LDO Regulator.

The LT3430/LT3430-1 are monolithic buck switching regulators that accept input voltages up to 60V. A high efficiency 3A, 0.1? switch is included on the die along with all the necessary oscillator, control and logic circuitry. A current mode architecture provides fast transient response and excellent loop stability.Special design techniques and a new high voltage process achieve high efficiency over a wide input range. Efficiency is maintained over a wide output current range by using the output to bias the circuitry and by utilizing a supply boost capacitor to saturate the power switch. Patented circuitry* maintains peak switch current over the full duty cycle range. A shutdown pin reduces supply current to 30?A and a SYNC pin can be externally synchronized with a logic level input from 228kHz to 700kHz for the LT3430 or from 125kHz to 250kHz for the LT3430-1.The LT3430/LT3430-1 are available in a thermally enhanced 16-pin TSSOP package.Applications Industrial and Automotive Power Supplies Portable Computers Battery Chargers Distributed Power Systems

DC473A: Demo Board for the LTC1702A - Dual 550kHz Synchronous 2-Phase Switching Regulator Controller.

The LTC3406B 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 with no load is 300?A and drops to <1?A in shutdown. The 2.5V to 5.5V input voltage range makes the LTC3406B ideally suited for single Li-Ion battery-powered applications. 100% duty cycle provides low dropout operation, extending battery life in portable systems. PWM pulse skipping mode operation provides very low output ripple voltage for noise sensitive applications.Switching frequency is internally set at 1.5MHz, allowing the use of small surface mount inductors and capacitors. The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode. Low output voltages are easily supported with the 0.6V feedback reference voltage. The LTC3406B is available in a low profile (1mm) ThinSOT package. Refer to LTC3406 for applications that require Burst Mode? operation. VOUT FSW Features LTC3406 Adj. 1.5MHz Burst Mode LTC3406-1.2 1.2V 1.5MHz Burst Mode LTC3406-1.5 1.5V 1.5MHz Burst Mode LTC3406-1.8 1.8V 1.5MHz Burst Mode LTC3406B Adj 1.5MHz Burst Mode Disabled LTC3406B-1.2 1.2V 1.5MHz Burst Mode Disabled LTC3406B-2 Adj. 2.25MHz Burst Mode Disabled LTC3406A Adj. 1.5MHz Low Ripple Burst Mode LTC3406AB Adj. 1.5MHz Burst Mode Disabled LTC3406AB-2 Adj. 2.25MHz Burst Mode Disabled Applications Cellular Telephones Personal Information Appliances Wireless and DSL Modems Digital Still Cameras MP3 Players Portable Instruments

Demonstration circuit DC500 is a constant-frequency step-down converter, using the various versions (fixed output/adjustable output/Burst Mode/Burst Mode defeated) of the LTC3406 or LTC3406B monolithic synchronous buck regulators. The DC500 has an input voltage range of 2.7V to 5.5V, and is capable of delivering up to 600 mA of output current at minimum input voltage of 3V. The DC500A-E features the 1.5V fixed output LTC3406B-1.5 (Burst Mode defeated).