Dynamic noise model and its application to high speed circuit design

A dynamic noise model is developed and applied to analyze the noise immunities of precharge-evaluate circuits. With cross-talk being the main source of noise injection in the circuit, a simple metric represented as voltage-time product can be used to quantify the dynamic noise-margin. This is verified through HSPICE simulation on DOMINO gates. Based on this dynamic noise model, a tool is developed and applied to find the static and dynamic noise-margins at various points in the circuit with the effects of charge share and power/ground bounce taken into account. Obtained noise-margins are translated into maximum allowable coupling capacitances between the nodes for different types of precharge-evaluate logic circuits. The results show the difference in dynamic noise immunities in different logic families. Accurate estimates of dynamic noise-margins and coupling capacitance bounds will help design robust CMOS circuits.