Patent ID: 7535739

Claim:
A semiconductor switch, comprising: a switching element; a control device for outputting a control signal to the switching element; an IC for supplying a control voltage to the control device; a power source for supplying a supply voltage to the switching element and the IC; wherein the control device is supplied with the control voltage within a predetermined range from the IC so that the control device outputs the control signal, wherein the switching element is turned on or off based upon the control signal from the control device, wherein the switching element includes a feed voltage-monitoring circuit for monitoring whether the control voltage fed from the IC to the control device is within the predetermined range, wherein the switching element further includes a driving circuit, wherein the driving circuit controls the switching element to be turned off when it is judged by the feed voltage-monitoring circuit that the control voltage is not within the predetermined range, and wherein the feed voltage monitoring circuit and the driving circuit are independently disposed from the IC.