Patent attributes
To prevent blowing of a fuse resistor due to application of static electricity to a trimming pad. In a fuse trimming circuit capable of switching the input level of a CMOS input circuit by supplying a voltage or a current to a trimming pad so as to blow a fuse resistor, a P-channel MOS transistor is inserted and connected between the trimming pad and the fuse resistor, and the MOS transistor is controlled to be turned on at a time of trimming. Thus, at the time of the trimming, electrical connection can be established between the trimming pad and the fuse resistor. At all times except the time of the trimming, electrical disconnection can be performed between the trimming pad and the fuse resistor if a control signal is not supplied to the control pad. Further, the parasitic diode of the MOS transistor functions as a static protection diode.
