Patent ID: 8008945

Claim:
A level-shift circuit that converts a first voltage level into a second voltage level different from the first voltage level, comprising: a low-side switch; a high-side switch connected to the low-side switch in series; a first capacitor into or from which an electric current flows according to a voltage fluctuation at a connection point of the low-side switch and the high-side switch; a second capacitor into or from which an electric current flows according to a voltage fluctuation at the connection point; an electric current detection circuit that detects at least one of the electric current flowing into or from the first capacitor and the electric current flowing into or from the second capacitor; a set level circuit that sets a logical voltage state of the second voltage level for driving the high-side switch based on the current flowing into or from the via a first capacitor; a reset level circuit that resets the logical voltage state of the second voltage level for driving the high-side switch based on the current flowing into or from the second capacitor; a drive circuit that on-off drives the high-side switch by a set signal of the set level circuit and a reset signal of the reset level circuit; and a mask circuit that masks at least one of a drive signal input into the set level circuit and a drive signal input into the reset level circuit during a period of time when the electric current detection circuit carries out the detection, the electric current flows into or from the first capacitor, and the electric current flows into or from the second capacitor.