Abstract. The paper proposes a simulation-based method for validating analog and mixed-signal circuits, using the hybrid systems methodology. This method builds upon RRT (Rapidly-exploring Random Trees), a probabilistic path/motion planning technique in robotics with a special property that allows to guarantee a good coverage quality. We focus on investigating conditions for preserving this coverage property and develop a variant of the classic RRTs which is more time-efficient. These results enabled us to implement a prototype tool that can handle high dimensional hybrid models.