Patent ID: 7733716
Filing Date: 2010-06-08
Classification: G06F,G11C

Abstract:
1. A signal masking circuit comprising: a detection circuit for detecting a period of a logic “L (Low)” preceding a period of a read data strobe signal effective for receiving read data, and generating a gating signal when the period of the logic “L” is equal to or longer than a predetermined period; a delayed read data strobe signal generation circuit for generating a delayed read data strobe signal by delaying the read data strobe signal; a gating circuit for gating the delayed read data strobe signal upon receipt of the gating signal, and generating a first masked read data strobe signal; a counting circuit for counting falls of the first masked read data strobe signal after the gating until counts counted by the counting circuit reaches a predetermined number, and generating a masking signal for masking the first masked read data strobe signal after the counting; and a masking circuit for masking the first masked read data strobe signal upon receipt of the masking signal, and outputting a second masked read data strobe signal.