Demo circuit 1069A is a monolithic step-down switching regulator with LDO featuring LT3500. The demo circuit is designed for 5.0V and 3.3V outputs from a 6V to 36V input. The LDO output is configured as a post-regulator of the switching regulator output. The total current capability is up to 2A. The switching regulator can be synchronized to an external clock input or be resistor-programmed to a 250kHz to 2.2MHz internal oscillator. Programmable frequency allows for optimization between efficiency and external component size. Cycle-by-cycle current limit, frequency foldback and thermal shutdown provide protections against a shorted output. The soft-start feature controls the ramp rate of the output voltage, eliminates input current surge during startup, and also provides output tracking.

DC1273A: Demo Board for LT1938 - 25V, 2.2A, 2.8MHz Step-Down Switching Regulator

DC1316A: Demo Board for LT1913 25V, 3.5A, 2.4MHz Step-Down Switching Regulator.

DC1313A: Demo Board for LT1912 36V, 2A, 500kHz Step-Down Switching Regulator.

DC697A: Demo Board for the LT1943 High Current Quad Output Regulator for TFT LCD Panels.

DC204A-B: Demo Board for the LT1776 Wide Input Range, High Efficiency, Step-Down Switching Regulator.

Demonstration circuit 3099A is a 42V, 5A synchronous step-down Silent Switcher® with spread spectrum frequency modulation featuring the LT8640A. The demo board is designed for 5V output from a 5.7V to 42V input. Meanwhile the LT8640A can operate down to 3.4V inputs. The wide input range allows a variety of input sources, such as automotive batteries and industrial supplies. The LT8640A is a compact, ultralow emission, high efficiency, and high speed synchronous monolithic stepdown switching regulator. The integrated power switches and inclusion of all necessary circuitry reduce the components count and solution size. Special Silent Switcher architecture minimizes EMI emissions. Selectable spread spectrum mode can further improve EMI performance. Ultralow 2.5μA quiescent current in Burst Mode® operation achieves high efficiency at very light loads. Fast minimum on-time of 30ns enables high VIN to low VOUT conversion at high frequency. The LT8640A switching frequency can be programmed either via oscillator resistor or external clock over a 200kHz to 3MHz range. The default frequency of demo circuit 3099A is 2MHz. The LT8640A SYNC/MODE pin on the demo board is grounded (JP1 at BURST position) by default for low ripple Burst Mode operation. Spread spectrum mode and forced continuous mode can be selected respectively by moving JP1 shunt. To synchronize to an external clock, move JP1 to FCM/SYNC and apply the external clock to the SYNC terminal. The LT8640A data sheet gives a complete description of the part, operation, and application information. The data sheet must be read in conjunction with this demo manual for demo circuit 3099A. The LT8640A is assembled in a 3mm × 4mm plastic QFN package with exposed pad for low thermal resistance. The layout recommendations for low EMI operation and maximum thermal performance are available in the data sheet section Low EMI PCB Layout and Thermal Considerations and Peak Output Current.

Demonstration circuit 1237A-A (LTC3527) and 1237A-B (LTC3527-1) are dual output, high-efficiency synchronous boost converter demo boards with each having an 800mA and a 400mA power switch. With a light load, the boost converters can startup with an input voltage as low as 700mV and once started, the input can go as low as 500mV while maintaining a regulated output voltage. Jumpers set the output voltages to one of three options for each output: 3V, 3.3V or 5V for VOUT1, and 1.8V, 2.85V or 3.3V for VOUT2. The devices can provide 200mA at 3.3V from a 1.5V input. The LTC3527-1 actively discharges VOUT1 or VOUT2 when the respective SHDN pin goes low.

DC238A: Demo Board for the LT1506 4.5A, 500kHz Step-Down Switching Regulator.

DC2985A is a multi-output power management solution demonstration circuit, featuring the LT3380. It contains two 2.5A, two 1.5A synchronous step-down DC/DC regulators and three 300mA LDO regulators. All regulators can be enabled with external enable pins. After the first regulator is enabled, the remaining enable pins use a precision threshold to allow hardwire-programmed Power-Up Sequence. A micro-USB communication interface is integrated on board to allow software GUI to write or read the registers in LT3380 via its I2C serial port. This GUI can control regulator enables, power-down sequencing, output voltage levels, dynamic voltage scaling, operation modes, status reporting and other special functions. Refer to LT3380 data sheet for more details on the electrical specifications and the setting of its command registers.