Dual High Efficiency PWM Step-Down DC/DC Converter

The RT8020H is a dual high efficiency Pulse-Width-Modulated (PWM) step-down DC/DC converter. It is capable of delivering 1A output current over a wide input voltage range from 2.5V to 5.5V. The RT8020H is ideally suited for portable electronic devices that are powered by 1-cell Li-ion battery or other power sources within the range such as cellular phones, PDAs and other hand-held devices. Two operational modes are available : PWM/Low-Dropout auto-switch mode and shutdown mode. Internal synchronous rectifier with low R_DS(ON) dramatically reduces conduction loss at PWM mode. No external Schottky diode is required in practical application.

The RT8020H enters Low-Dropout mode when normal PWM cannot provide regulated output voltage by continuously turning on the upper PMOS. The RT8020H enters shutdown mode and consumes less than 0.1μA when the EN pin is pulled low.

The switching ripple is easily smoothed-out by small package filtering elements due to a fixed operation frequency of 1.5MHz. This, along with a small WDFN-12L 3x3 package, provides an ideal solution for small PCB area application. Other features include soft start, lower internal reference voltage with 2% accuracy, over temperature protection, and over current protection.