| 摘要 |
PROBLEM TO BE SOLVED: To curb an increase in I/O pads of a semiconductor device (LSI) and maintain high security by making analysis of the semiconductor device (LSI) internal from external impossible. SOLUTION: In the semiconductor device, an input enabling pad 21 which is common to all I/O pads for tests is provided to a pad part 12, and a pad 22 for comparison signals is provided to an adjacent LSI 11 on a wafer. a signal comparing part 19 compares signals of the input enabling pad 21 and the pad 22 for comparison signals adjacent to the LSI on the wafer. If result matches, an I/O pad 14 becomes usable. In a product, since a wiring layer 26 to a comparator 20 is electrically cut from the pad 22 for comparison signals by separating the LSI 11 with a scribe line 23, the I/O pad becomes nonusable after separating the LSI 11 by a scribe line 23, therefore analysis from external becomes impossible. COPYRIGHT: (C)2005,JPO&NCIPI
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