SIGNAL-INSPECTING CIRCUIT

摘要

PROBLEM TO BE SOLVED: To reduce a scale of a test circuit for facilitating an LSI inspection by realizing a periodic inspection, a jitter inspection and a duty guarantee inspection for periodic signals by simple circuits respectively at a shipping inspection time to LSIs. SOLUTION: The signal-inspecting circuit 102 outputs the result of calculating an AND (or OR) of a signal to be measured, a signal having a phase difference of a jitter guarantee amount to the signal to be measured, and an inverted signal delayed by a guarantee period; and judges the LSI as good when the output is always Low (or High). The period inspection can thus be realized by the simple circuit.