Patent ID: 7482789

Claim:
A step-up converter for generating an output voltage that is greater than an input voltage, comprising: an inductor receiving the input voltage at one end; a main switch connected to the other end of the inductor for allowing/interrupting the passage of a current from the inductor; a first switch connected to the other end of the inductor for allowing/interrupting a current output from the other end of the inductor to pass the current in both directions; a smoother connected to the other end of the inductor through the first switch; and a current detection circuit for detecting a current flowing from the inductor to the main switch irrespective of whether a value of the current is positive or negative to output a current detection signal, wherein the current detection circuit includes: a first detection circuit for detecting the current flowing from the inductor to the main switch when the value of the current is positive; and a second detection circuit for detecting the current flowing from the inductor to the main switch when the value of the current is negative.