| 摘要 |
PURPOSE:To terminate the confirmation of the operation of a counter in a short time by enabling each counter only when the operation of the counter is confirmed and outputting an output of each counter from a respective output terminal. CONSTITUTION:In the case of confirming the operation of counters 1 -3, when a test signal TEST is set to logical 1 in the test mode, an output of a carry terminal CRY of the counters 1-3 is outputted from output terminals 7-9 of a large scale integrated circuit. Moreover, since a logical 1 is outputted from a 2nd output terminal E of signal switching circuits 4, 5 in this case, logical 1 is inputted to an enable terminal EN of the counters 1-3 and the counters 1-3 are operated in parallel. When a clock CLK is inputted, logical 1 is outputted from the output terminals 7-9. The output is monitored and whether or not the output reaches logical 1 by a specified clock number to confirm the operation of the counters 1-3. |
