Power by Linear™ / Analog Devices' LT3740 is a synchronous step-down switching regulator controller. It drives N-channel power MOSFET stages. It uses valley current mode architecture to achieve very low duty cycles with excellent transient response without requiring a sense resistor.

The LT3740 includes an internal step-up converter to provide a bias 7.8 V higher than the input voltage for the drive. This enables the part to work from an input voltage as low as 2.2 V. The XREF pin is an external reference input that allows the user to override the internal 0.8 V feedback reference with any lower value, allowing full control of the output voltage during operation, output voltage tracking or soft-start. The controller has three current limit levels that can be chosen by connecting the RANGE pin to ground, open, and input respectively.

The LT3740 comes in a small (5 x 3) 16-pin DFN package that has an operating temperature range of -40°C to +85°C. The LT3740 is ideal for portable, handheld industrial, and test and measurement applications.