The RT8020J 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 RT8020J is ideally suited for portable electronic devices that are powered from 1-cell Li-ion battery or from 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 and shutdown modes. Internal synchronous rectifier with low RDS(ON) dramatically reduces conduction loss at PWM mode. No external Schottky diode is required in practical application. 
The RT8020J enters Low-Dropout mode when normal PWM cannot provide regulated output voltage by continuously turning on the upper P-MOSFET. The RT8020J enter shutdown mode and consumes less than 0.1μA when 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 small WDFN-12L 3x3 package provides small PCB area application. Other features include soft start, lower internal reference voltage with 2% accuracy, over temperature protection, and over current protection.
        
        
        
        
        
        
            
            Applications
            
                -  Mobile Phones
 
-  Personal Information Appliances
 
-  Wireless and DSL Modems
 
-  MP3 Players
 
-  Portable Instruments