Effects of parameter variations and crosstalk on H-tree clock distribution networks

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 (V_DD), temperature, and gate oxide thickness (t_OX) on the clock signal delay and transition time are evaluated. In addition to parameter variations, crosstalk effects among the H-tree structure and other interconnect wires are investigated. It is shown that the delay and transition time of the clock signal is spatially dependent on interconnect crosstalk along an H-tree