Patent ID: 7936156
Filing Date: 2011-05-03
Classification: H02M,Y02B

Abstract:
1. A DC-DC converter, comprising: a first transistor coupled to a first power supply line and having a first conductivity type; a second transistor coupled between the first transistor and a second power supply line, and having the first conductivity type; an output unit driving a first control signal causing the first transistor to become conductive, based on a drive voltage, and outputting the first control signal to the first transistor; a boot strap circuit including a capacitor having a first end coupled to a node of the first transistor and the second transistor and supplying the output unit with the drive voltage based on the capacitor, wherein an electric potential of the first end is reduced before the first transistor becomes conductive; and a first switch coupling and decoupling the first end of the capacitor and the second power supply line, wherein an electric potential of the first power supply line is higher than an electric potential of the second power supply line, and the first switch couples the first end and the second power supply line in response to the first control signal, and reduces the electric potential of the first end.