POWER SUPPLY CIRCUIT AND SENSING CIRCUIT

摘要

A power supply circuit comprises: a switching element which supplies power to a load when a drive signal is inputted; a drive signal generating unit further comprising a resistor and a PN junction which are serially connected to a power source; and a switch which is connected in parallel to the PN junction. The PN junction is connected in the forward direction with respect to the voltage of the power source, and the generating unit outputs the drive signal to the switching element with the switch in the closed state.