SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE

摘要

PROBLEM TO BE SOLVED: To conduct a test, by providing a plurality of switching circuit on the first wiring for switching whether connecting between first wirings or cutting the first wirings and connecting a first wiring and a third wiring according to the control signal inputted via a second wiring. SOLUTION: When testing DRAM 2, a control signal is set, one of AND gates is prohibited and the other is allowed. Thus, the input of DRAM 2 is cut from the terminal of CPU and LOGIC 4, ordinary signal of the terminal of CPU and LOGIC 4 is cut from the output of DRAM 2 and the input of DRAM 2 from testing input and testing output from the output of DRAM 2 become effective. Then a test pattern is inputted from testing input, data is written from the input of DRAM 2 and the test pattern data is read out of the output of DRAM 2 and outputted from the testing output. According to the comparison of input and output data, good or bad of DRAM 2 is judged.