Abstract: A level shifter circuit includes a level shifter unit and a latch unit. The level shifter unit receives two complementary input signals and converts the voltage levels of two complementary input signals. The latch unit latches the state of two output nodes before the low voltage supply is turned off. On condition that the low voltage supply is off, the level shifter circuit avoids current drainage and ensures the voltage level of the output. The invention has the advantages of small circuit size and being easy to design.

Abstract: A USB apparatus capable of automatically detecting a USB mode and the method thereof, which determines the USB apparatus to act as a host or device function in accordance with electrical signals on two connective ports and uses an internal or external switch to route USB signals to an appropriate connection port. Therefore, a user can connect the USB apparatus with other OTG-USB apparatuses or a typical USB host or device without preparing any additional cables, and a mode of the USB apparatus is automatically detected and set to thus increase the convenience in usage.

Abstract: A level shifter circuit includes a level shifter unit and a latch unit. The level shifter unit receives two complementary input signals and converts the voltage levels of two complementary input signals. The latch unit latches the state of two output nodes before the low voltage supply is turned off. On condition that the low voltage supply is off, the level shifter circuit avoids current drainage and ensures the voltage level of the output. The invention has the advantages of small circuit size and being easy to design.