Semiconductor integrated circuit provided with input protection device, assembly circuit board of the semiconductor integrated circuit, and method of removing the input protection function

摘要

The present invention is intended to prevent an element breakdown derived from an electrostatic discharge (ESD) during the handling such as packaging of an LSI chip, packing and transportation, and to divide the input protection diodes from the signal input terminal during the ordinary use of the LSI so as to prevent the inhibition of a high speed operation and a latch-up phenomenon. The first and second diodes, each connected in reverse polarity between the signal input terminal and any of a voltage supply node and a ground node inside the LSI, are divided from the signal input terminal of the LSI by controlling the first and second fuse elements, each connected between the signal input terminal and any of the first and second diodes, from the outside after the LSI is mounted to the assembly circuit board.