SEMICONDUCTOR INTEGRATED CIRCUIT AND METHOD OF MEASURING ITS OUTPUT DELAY FROM

摘要

PROBLEM TO BE SOLVED: To accurately measure a delay time of an output circuit at no-load. SOLUTION: With an opening and closing switch 19 closed, a first delay time ta for a distance between a flip-flop 11 of an output circuit 4 and a first comparator 26 and a second delay time tb1 for a distance between the flip-flop 11 and a second comparator 28 are measured using an LSI chip 1 having a test circuit 5 mounted thereon. Next, with the opening and closing switch 19 opened, a third delay time tb2 for a distance between the flip-flop 11 and a second comparator 19 is measured. Based on the measured results, an increment dt=(tb1-tb2) of the delay time due to an incidental capacity comprising a wiring capacity 23 and a pin input capacity 29 is calculated, and the delay time t0=(ta-dt) of an output circuit 4 at no-load is obtained.