Coupling effect due to line-to-line capacitance is of serious concern in timing analysis of circuits in ultra deep submicron CMOS technology. Often coupling delay is strongly dependent on temporal correlation of signal switching in relevant wires. Temporal decorrelation by shifting timing window can alleviate performance degradation induced by tight coupling. This paper presents an algorithm for minimizing circuit delay through timing window modulation in dual V/sub t/ technology. Experimental results on the ISCAS85 benchmark circuits indicate that the critical delay will be reduced significantly when low V/sub t/ is applied properly.