Input DC/DC controller drives N-channel MOSFETs and delivers as much as 20 amps

Linear Technology Corp. in Milpitas, Calif., is offering the LTC3822, a 2.75-to-4.5-volt input synchronous step-down DC/DC controller that drives N-channel MOSFETs without requiring an external supply for gate drive. In addition, the LTC3822 eliminates the need for a sense resistor by using MOSFET RDS(ON) sensing current, which improves efficiency and reduces solution cost. Although the LTC3822 drives N-channel MOSFETs, it can operate at 99 percent duty cycle for very low dropout regulation. An adjustable operating frequency from 300 kHz to 750 kHz allows designers to size their systems, minimize noise interference and optimize efficiency. The LTC3822 comes in two packages a 10-lead MSOP and a smaller 3 × 3 mm DFN. It is rated for operation from -40°C to 85°C. For more information contact the company online at www.linear.com.