Parameter variations and crosstalk noise effects on high performance H-tree clock distribution networks

Abstract

Controlling the delay and the transition time of the clock signal in the presence of various noise sources, process parameter variations and environmental effects represents a fundamental problem in the design of high speed synchronous circuits. The effects of parameter variations and crosstalk noise on the clock signal propagating along an H-tree clock distribution network are investigated in this paper. In particular, the effects of variations in power supply voltage (V DD), temperature, and gate oxide thickness (t ox) on the delay and the transition time of the clock signal are evaluated. Furthermore, the effects of crosstalk between an H-tree structure and other interconnect wires are investigated. Different scenarios of capacitive coupling along different spatial locations of an H-tree are considered. The effects of coupling on the propagation delay, the transition time, and the waveform shape of the clock signal are demonstrated.