In a typical synchronous SoC design, a huge peak current often occurs near the time of an active clock edge because of aggregate switching of a large number of transistors. The number of aggregate switching transistors can be lessened if the SoC design can use a clock scheme of mixed rising and falling triggering edges rather than one of pure rising (falling) triggering edges. In this paper, we propose a clock-triggering-edge assignment technique and algorithms that can assign either a rising triggering edge or a falling triggering edge to each clock of each IP core or block of a given IP-based SoC design. The goal of the algorithms is to reduce the peak current of the design. Experimental results show that our algorithms can reduce peak currents up to 56.3%.