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 start-up 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

Demonstration circuit DC2907A features the LT8338, a low IQ, Synchronous Boost Converter in a thermally enhanced 10-lead plastic MSOP package. DC2907A is designed to convert a 4V to 16V source to 24V output, with up to 460mA of load current, depending on the input voltage. It was designed with a switching frequency of 2.2MHz. DC2907A contains a selectable jumper, JP1, to aid in the selection of any of the five modes of operation. The default setting is Burst mode. This converter features Spread Spectrum Frequency Modulation, SSFM. The input and output filters installed on the PCB help suppress EMI noise, but the use of SSFM makes it easier to pass CISPR25 class 5 conducted and radiated emissions testing for automotive vehicles. To perform an EMI evaluation for this converter include the input filter by connecting the input source to the VEMI terminal and select the Burst+SSFM JP1 setting. EMI filters may not be necessary for all applications. For a lower parts count and BOM cost EMI filters can be removed. To do so, replace FB1 and FB2 with a zero ohm jumpers and remove all input and output filter components located inside the dashed-line rectangles on the schematic, plus C1 and C13. Proper board layout is essential for maximum thermal performance. See the datasheet section “Thermal Considerations”. The Performance Summary section details the ratings of the DC2907A at room temperature. The LT8338 datasheet gives a complete description of the part, operation and application information. The data sheet must be read in conjunction with this quick start guide for DC2907A. The LT8338 is available in a thermally-enhanced 10 lead plastic MSOP package.

DC290A-B: Demo Board for the LTC1878 High Efficiency Monolithic Synchronous Step-Down Regulator.

Demonstration circuit 1156A is an ultralow quiescent current and low dropout voltage linear regulator featuring the 20mA output current LT3009 in the  which comes in the 2mm × 2mm DFN package. The DC1156A has an input voltage range from 1.6V to 20V and has jumper-selectable output voltages of 1.2V, 1.5V, 1.8V, 2.0V, 2.5V, 3.3V, 5V or a user-defined value. With the 3µA quiescent current of the LT3009, the DC1156A is ideal for supplying power to low current battery-powered systems, keep-alive power supply and remote monitoring utility meters and hotel door locks.

Demonstration circuit 879 is a Micropower Synchronous Step-Up Converter with Output Disconnect featuring the LTC3525-3.3 and LTC3525-5. The LTC3525 is a high performance Burst Mode operation only, synchronous boost converter. The LTC3525 incorporates a feature that maximizes efficiency by adjusting the peak and valley of the inductor current as a function of load. The demo board has two assembly versions: DC879A-A and DC879A-B. The DC879A-A offers fixed 3.3V output. The DC879A-B offers fixed 5V output. They offer a compact, high efficiency solution in single cell or dual cell alkaline or Li-ion applications. Only three small external components are required.

DC1296A: Demo Board for the LTC3556 High Efficiency USB Power Manager with Dual Buck and Buck-Boost DC/DCs

DC1300A-B: Demo Board for: LTC3725 - Single-Switch Forward Controller and Gate Driver LTC3726 - Secondary-Side Synchronous Forward Controller

Demonstration circuit 2911A is an IEEE 802.3bt compliant and LTPoE++ interoperable Power over Ethernet (PoE) Powered Device (PD). It features the LT4293 PD interface controller and the LT4321 PoE ideal diode bridge controller. The LT4293 provides LTPoE++, IEEE 802.3af (PoE, Type 1), IEEE 802.3at (PoE+, Type 2), and IEEE 802.3bt (PoE++, Type 3 and 4) compliant interfacing. It utilizes an external, low RDS(ON) (30mΩ typical) N-channel MOSFET for the Hot Swap function to improve efficiency. Power good (PWRGD) output indicates the PD controller is ready to provide power to the downstream load. This signal can be used to enable an isolated power supply. The T2P output indicates the available power from the Power Sourcing Equipment (PSE). This signal communicates allocated power from either LTPoE++ or IEEE 802.3bt-compliant PSEs to the downstream PD circuitry. The LT4321 controls eight low RDS(ON) (57mΩ typical) N-channel MOSFETs to further improve end-to-end power delivery efficiency and ease thermal design. This solution replaces the eight diodes typically found in a passive PoE rectifier bridge. The DC2911A accepts up to 90W of delivered power from a PSE via the RJ45 connector (J1) or a local 48V DC power supply using the auxiliary supply input. When both supplies are connected, the auxiliary supply input has priority over the PoE input.

Demonstration circuit 719 is an Isolated Full-Bridge Converter with Synchronous Rectification featuring the LTC3723-1, LTC3901, LTC4440, and LT1431. It operates at 300kHz and produces a regulated 12V, 20A output in a quarter-brick footprint from a typical telecom input voltage range of 42 to 56V. Synchronous rectification helps to attain efficiency approaching 96%. Isolation voltage is 1500VDC.

Demonstration circuit 2599A features the LT8361 in a SEPIC configuration. It operates with a switching frequency of 400kHz and is designed to convert a 4.5V to 48V source to 24V, with up to 600mA output current (depending on input voltage). The LT8361 can operate with inputs as high as 60V. However, in this demo circuit, the input is limited by the voltage rating of the input capacitors. The demo board contains a selectable jumper, JP1, to aid in the selection of the desired Sync pin mode of operation. The default setting is Burst Mode® operation. This layout is optimized for good EMI performance and small solution size. Input and output filters and an optimized power switching loop, comprised of C20 and C21 are necessary to pass CISPR 25 Class 5 emissions, and are added by default. These components can be excluded in applications not requiring noise immunity. The data sheet gives a complete description of the device, operation and application information. The data sheet must be read in conjunction with this demo manual.