Patent ID: 7504807

Claim:
A switching regulator comprising: an input terminal connected to a supply voltage source; an output terminal connected to a load operable in a normal operating mode and a standby mode; a voltage step up/step down DC/DC converter for converting a power input voltage from said supply voltage source to a first set voltage corresponding to the normal operating mode, thereby generating a power output voltage at an output node of the voltage step up/step down DC/DC converter; a voltage step up DC/DC converter for converting the power input voltage from said supply voltage source to a second set voltage corresponding to the standby mode, when a power output voltage of the step up DC/DC converter is equal to or lower than the second set voltage which is lower than the first set voltage, and for allowing the power input voltage from the supply voltage source to pass without any conversion to the second set voltage when the power output voltage exceeds the second set voltage, thereby generating the power output voltage of the step up DC/DC converter at an output node of the step up DC/DC converter; and a mode switching switch for connecting said output terminal and the output node of said voltage step up/step down DC/DC converter in the normal operating mode, and connecting said output terminal and the output node of said voltage step up DC/DC converter in the standby mode.