RT8099

® RT8099 1.5MHz, 600mA, High Efficiency PWM Step-Down Converter General Description The RT8099 is a Pulse-Width-Modulated (PWM) DC/DC step-down converter, and is capable of delivering 0.6A output current over a wide input voltage range from 2.7V to 5.5V. The RT8099 is ideally suited for portable electronic devices that are powered from 1-cell Li-ion battery such as cellular phones, PDAs and handyterminals. Internal synchronous rectifier with low RDS(ON) dramatically reduces conduction loss at PWM mode. No external schottky barrier diode is required in practical application. The RT8099 enters low-dropout mode when normal PWM cannot provide regulated output voltage by continuously turning on the high-side P-MOSFET. The RT8099 enters shut-down 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 1.5MHz high switching frequency. Other features include soft-start, auto discharge, lower internal reference voltage, over-temperature protection, and over-current protection. The RT8099 is available in the small UDFN-6L 1.6x1.6 package for saving PCB space. Features  2.7V to 5.5V Input Range  Adjustable Output from 0.7V to 5V  0.6A Output Current  95% Efficiency  No Schottky Barrier Diode Required  1.5MHz Spread Spectrum Frequency PWM Operation  Auto Discharge Function  Over-Current Protection  Overt-Temperature Protection  Integrated Soft-Start Function  Small 6-Lead UDFN Pa...