The LM3370 is a dual step-down DC-DC converter optimized for powering ultra-low voltage circuits from a single Li-Ion battery and input rail ranging from 2.7V to 5.5V. It provides two outputs with 600 mA load per channel. The output voltage range varies from 1V to 3.3V and can be dynamically controlled using the I 2C compatible interface. This dynamic voltage scaling function allows processors to achieve maximum performance at the lowest power level. The I 2C compatible interface can also be used to control auto PFM-PWM/PWM mode selection and other performance enhancing features. The LM3370 offers superior features and performance for portable systems with complex power management requirements. Automatic intelligent switching between PWM low-noise and PFM low-current mode offers improved system efficiency. Internal synchronous rectification enhances the converter efficiency without the use of further external devices. There is a power-on-reset function that monitors the level of the output voltage to avoid unexpected power losses. The independent enable pin for each output allows for simple and effective power sequencing. LM3370 is available in a 4 mm by 5 mm 16-lead non-pullback LLP and a 20-Bump micro SMD, 3.0 mm x 2.0 mm x 0.6 mm, package. A high switching frequency—2 MHz (typ)—allows use of tiny surface-mount components including a 2.2 µH inductor. Default fixed voltages for the 2 output voltages combination can be customized to fit system requirements by contacting National Semiconductor Corporation.