Patent ID: 8373401
Filing Date: 2013-02-12
Classification: H02M

Abstract:
1. A step-up/step-down DC-DC converter comprising: a voltage decrease section having a voltage decrease switch for inputting a DC voltage from a DC power supply and a choke coil connected to the voltage decrease switch, the voltage decrease section for outputting an output voltage lower than an input voltage; a voltage increase section having a voltage increase switch connected to the voltage decrease switch through the choke coil, the voltage increase section for outputting an output voltage higher than an input voltage; and a control section for providing control to turn on and off the voltage decrease switch and the voltage increase switch, wherein the control section comprises: wherein, when the voltage value of the computation output voltage does not exist between the first voltage value and the second preset voltage value, the drive pulse generation section provides control to set a voltage decrease mode for maintaining the voltage increase switch off and turning on and off the voltage decrease switch, or to set a voltage increase mode for maintaining the voltage decrease switch on and turning on and off the voltage increase switch, and when the voltage value of the computation output voltage exists between the first voltage value and a second voltage value, the drive pulse generation section provides control to set a voltage increase and decrease mix mode for selectively switching the on and off operation of the voltage decrease switch and the on and off operation of the voltage increase switch.