Demonstration circuit 516A-A is a low output voltage, synchronous boost converter featuring the LTC3423. The LTC3423 is ideal for applications that require an output voltage between 1.5V to 2.6V from a single alkaline or NiCd/NiMH cell. A bias voltage (VDD) of 2.7V to 5.5V is required to power the internal circuitry. The input voltage (VIN) range is 1V to 1.6V, but once up and running, the device can operate with an input voltage as low as 0.5V. The output voltage is set at 1.8V. For a 1V minimum battery voltage, the LTC3423 can provide 350mA.

Demonstration circuit 533 is an 800kHz adjustable output boost regulator featuring the LT3436. This current-mode control monolithic (switch included) converter has a wide operating supply voltage of 3V to 25V and a minimum peak switch current rating of 3A, though the demo board has a reduced input voltage range of 3.2V to 12V. It provides 12V at 550mA from a 3.3V input and 12V at 900mA from a 5V input.

Demonstration circuit 534 is a fast transient response, very low dropout linear regulator featuring the 4A output current LT3150 linear regulator controller. The DC534 has an input voltage range of 1.1V to 10V and generates a jumper-selectable output voltage of 1.2V, 1.5V or 1.8V. With the LT3150 driving external N-channel MOSFETs as source followers, the DC534 can produce very fast transient response. The proper selection of the Rds(on) of the MOSFETs allows dropout voltages below 300 mV. These capabilities, plus its ability to maintain stable operation with ceramic output capacitors, make the DC534 voltage regulator ideally suited for low VIN-to-VOUT applications, such as microprocessor/microcontroller/FPGA power supplies.

DC536A-B: Demo Board for the LTC4211 Hot Swap Controller with Multifunction Current Control.

Demonstration circuit 536B is a hot swap controller with multifunction current control featuring the LTC4211. The DC536B-A is configured to operate with up to 7A load and DC536B-B up to 20A load.

Demonstration circuit 542 is a dual output, dual phase synchronous step-down controller, featuring the LTC3728EG. Output #1 can be configured for either 5.0V or 3.3V and output #2 can be configured for either 3.3V or 2.5V. The maximum load for both rails is 12A. The input voltage range of the DC542 is 8V to 24V. The DC542 also contains a footprint for a 5.5V boost converter bias supply whose output is connected to EXTVCC. See the “Optional Bias Supply” section for more details.

DC551A-B: Demo Board for the LTC4002-4.2 Standalone Li-Ion Switch Mode Battery Charger.

DC606A: Demo Board for the LTC4056-4.2 Linear Li-Ion Charger with Termination in ThinSOT.

Demonstration Circuit 616 is a synchronous, 4-phase boost converter using the LTC3425. It is capable of operating below 1V input. DC616A is set for 3.3V output. DC616B is set for 5V output. On each demo board, the left circuit gives higher efficiency and current rating; while the right circuit has smaller size and lower cost. The switching frequency is set at 1MHz per phase, minimizing inductor and capacitor size. A single resistor at RT pin sets the frequency. If desired, the LTC3425 can be synchronized to an external clock.

The LT3781 controller simplifies the design of high power synchronous dual transistor forward DC/DC converters. The part employs fixed frequency current mode control and supports both isolated and nonisolated topologies. The IC drives external N-channel power MOSFETs and operates with input voltages up to 72V.The LT3781 is ideal for output derived power schemes, through the use of a large undervoltage lockout hysteresis range. The part is also equipped with an 18V VCC shunt regulator, which prevents exceeding absolute maximum ratings while in trickle start applications.The LT3781?s operating frequency is programmable and can be synchronized up to 350kHz. Switch phase is also controlled during synchronized operation to accommodate multiple-converter systems. Internal logic guarantees 50% maximum duty cycle operation to prevent transformer saturation.The LT3781 is available in a 20-lead SSOP package.Applications Isolated Telecommunication Systems Personal Computers and Peripherals Distributed Power Step-Down Converters Lead Acid Battery Backup Systems Automotive and Heavy Equipment