The LTC1474/LTC1475 series are high efficiency step-down converters with internal P-channel MOSFET power switches that draw only 10?A typical DC supply current at no load while maintaining output voltage. The LTC1474 uses logic-controlled shutdown while the LTC1475 features pushbutton on/off. The low supply current coupled with Burst Mode? operation enables the LTC1474/LTC1475 to maintain high efficiency over a wide range of loads. These features, along with their capability of 100% duty cycle for low dropout and wide input supply range, make the LTC1474/LTC1475 ideal for moderate current (up to 300mA) battery-powered applications. The peak switch current is user-programmable with an optional sense resistor (defaults to 325mA minimum if not used) providing a simple means for optimizing the design for lower current applications. The peak current control also provides short-circuit protection and excellent startup behavior. A low-battery detector that remains functional in shutdown is provided . The LTC1474/LTC1475 series availability in 8-lead MSOP and SO packages and need for few additional components provide for a minimum area solution.Applications Cellular Telephones and Wireless Modems 4mA to 20mA Current Loop Step-Down Converter Portable Instruments Battery-Operated Digital Devices Battery Chargers Inverting Converters Intrinsic Safety Applications

Demo Circuit 1467 is a high efficiency, high frequency step-down converter, incorporating the LTC3614 monolithic synchronous regulator. The DC1467A has an input voltage range of 2.25V to 5.5V, and is capable of delivering up to 4A of output current. The output voltage of the DC1467A can be set as low as 0.6V, the reference voltage of the LTC3614. The operating frequency range of the DC1467A is either set to a fixed 2.25 MHz by connecting the frequency pin to SVin, set by an external resistor, or synchronized to an external clock, with a range up to 4 MHz. At low load currents, the DC1467A can operate in either noise sensitive applications, due to the capability of the LTC3614 to operate in pulse-skipping mode, or in high efficiency applications, because the LTC3614 also has Burst-Mode capability. The Burst Mode clamp can be set externally.

Demonstration circuit 1471 is a monolithic step-down DC/DC switching regulator featuring the LT3990. The switching frequency is adjustable up to 2.2MHz. The demo circuit is designed for 5V, 350mA output from a 6.5V to 62V input. The wide input range of the LT3990 allows a variety of input sources including automotive batteries and 24V industrial supplies. Low ripple Burst Mode increases the efficiency at the light load while keeping the output ripple below 5mV in a typical application. The part is in shutdown when the EN pin is low and active when the pin is high. The threshold of the EN pin is accurate at 1V when VIN is above 4.2V. Adding a resistor divider from VIN to EN can program the LT3990 to regulate the output only when VIN is above a desired voltage. The catch diode and boost diode are integrated to reduce the components count and solution size. The circuit consumes only 2.5μA of quiescent current.

The LT1339 is a high power synchronous current mode switching regulator controller. The IC drives dual N-channel MOSFETs to create a single IC solution for high power DC/DC converters in applications up to 60V.The LT1339 incorporates programmable average current limiting, allowing accurate limiting of DC load current independent of inductor ripple current. The IC also incorporates user-adjustable slope compensation for minimization of magnetics at duty cycles up to 90%.The LT1339 timing oscillator operating frequency is programmable and can be synchronized up to 150kHz. Minimum off-time operation provides main switch protection. The IC also incorporates a soft start feature that is gated by both shutdown and undervoltage lockout conditions.An output phase reversal pin allows flexibility in configuration of converter types, including inverting and negative topologies.Applications 48V Telecom Power Supplies Personal Computers and Peripherals Distributed Power Converters Industrial Control Systems Lead-Acid Battery Backup Systems Automotive and Heavy Equipment

Demonstration circuit 1516A is a 1.5V/15A synchronous buck converter operating with a switching frequency of 300kHz over an input voltage range of 4.5V to 24V. The demo board comes in two versions. The -A version uses inductor DCR current sensing with an iron powder inductor for highest efficiency. The -B version uses a 2.5mΩ/1% sense resistor for accurate current sensing with a low DCR ferrite inductor. The fixed on-time valley current mode control of the LTC3833 allows for a fast load step response.

Demonstration circuit 1516A is a 1.5V/15A synchronous buck converter operating with a switching frequency of 300kHz over an input voltage range of 4.5V to 24V. The demo board comes in two versions. The -A version uses inductor DCR current sensing with an iron powder inductor for highest efficiency. The -B version uses a 2.5mΩ/1% sense resistor for accurate current sensing with a low DCR ferrite inductor. The fixed on-time valley current mode control of the LTC3833 allows for a fast load step response.

The LTC3789 is a high performance buck-boost switching regulator controller that operates from input voltages above, below or equal to the output voltage. The constant-frequency, current mode architecture allows a phase-lockable frequency of up to 600kHz, while an output current feedback loop provides support for battery charging. With a wide 4V to 38V (40V maximum) input and output range and seamless, low noise transitions between operating regions, the LTC3789 is ideal for automotive, telecom and battery-powered systems.The operating mode of the controller is determined through the MODE/PLLIN pin. The MODE/PLLIN pin can select between pulse-skipping mode and forced continuous mode operation and allows the IC to be synchronized to an external clock. Pulse-skipping mode offers high efficiency and low ripple at light loads, while forced continuous mode operates at a constant frequency for noise-sensitive applications.A PGOOD pin indicates when the output is within 10% of its designed set point. The LTC3789 is available in low profile 28-pin 4mm ? 5mm QFN and narrow SSOP packages.Applications Automotive Systems Distributed DC Power Systems High Power Battery-Operated Devices Industrial Control

The LTC2977 is an 8-channel Power System Manager used to sequence, trim (servo), margin, supervise, manage faults, provide telemetry and create fault logs. PMBus commands support power supply sequencing, precision point-of-load voltage adjustment and margining. DACs use a proprietary soft-connect algorithm to minimize supply disturbances. Supervisory functions include overvoltage and undervoltage threshold limits for eight power supply output channels and one power supply input channel, as well as over and under temperature limits. Programmable fault responses can disable the power supplies with optional retry after a fault is detected. Faults that disable a power supply can automatically trigger black box EEPROM storage of fault status and associated telemetry. An internal 16-bit ADC monitors eight output voltages, one input voltage, and die temperature. In addition, odd numbered channels can be configured to measure the voltage across a current sense resistor. A programmable watchdog timer monitors microprocessor activity for a stalled condition and resets the microprocessor if necessary. A single wire bus synchronizes power supplies across multiple LTC Power System Management (PSM) devices. Configuration EEPROM with ECC supports autonomous operation without additional software.APPLICATIONS Computers and Network Servers Industrial Test and Measurement High Reliability Systems Medical Imaging Video

The LTC3553 is a micropower, highly integrated power management and battery charger IC for single-cell Li-Ion/Polymer battery applications. It includes a PowerPath manager with automatic load prioritization, a battery charger, an ideal diode and numerous internal protection features. Designed specifically for USB applications, the LTC3553 power manager automatically limits input current to a maximum of either 100mA or 500mA. Battery charge current is automatically reduced such that the sum of the load current and the charge current does not exceed the selected input current limit. The LTC3553 also includes a synchronous buck regulator, a low dropout linear regulator (LDO), and a pushbutton controller. With all supplies enabled in standby mode, the quiescent current drawn from the battery is only 12?A. The LTC3553 is available in a 3mm ? 3mm ? 0.75mm 20-pin QFN package. Option LDO PGOOD Hard Reset Time LTC3553 ON/OFF Control No 5 Seconds LTC3553-2 Always On Yes 14 Seconds Applications USB-Based Handheld Products Portable Li-Ion/Polymer Based Electronic Devices Wearable Electronics Low Power Medical Devices

The LTC4365 protects applications where power supply input voltages may be too high, too low or even negative. It does this by controlling the gate voltages of a pair of external N-channel MOSFETs to ensure that the output stays within a safe operating range.The LTC4365 can withstand voltages between ?40V and 60V and has an operating range of 2.5V to 34V, while consuming only 125?A in normal operation.Two comparator inputs allow configuration of the overvoltage (OV) and undervoltage (UV) set points using an external resistive divider. A shutdown pin provides external control for enabling and disabling the MOSFETs as well as placing the device in a low current shutdown state. A fault output provides status of the gate pin pulling low. A fault is indicated when the part is in shutdown or the input voltage is outside the UV and OV set points.The LTC4365 has a 36ms turn-on delay that debounces live connections and blocks 50Hz to 60Hz AC power. For fast recovery after faults, the LTC4365-1 has a reduced 1ms turn-on delay.Applications Portable Instrumentation Industrial Automation Laptops Automotive Surge Protection