| 摘要 |
PURPOSE:To easily confirm the function of a counter within a short time by incorporating a multivibrator in the test circuit of the counter of a semiconductor integrated circuit. CONSTITUTION:A selector 2 is changed over to a usual input state and a test input state by the change-over control due to a control signal. At the time of test input, a multivibrator 3 is operated by a signal clock and the output signal thereof is inputted to the respective clock terminals of counters 5 - 8 through the selector 2. In this case, an arbitrary number of pulses are continued until the carry signals of these counters are outputted after the output signal is inputted to the clock terminals of the counter 5 - 8 and counted by a counter 4. In the function test of the counter 4, the counter 4 can be tested within a short time without being divided and the confirmation of planned function is easily executed. |
