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A macromodeling and timing simulation technique is presented that allows fast, accurate delay calculations for CMOS circuits. This method is well suited for delay calculations of regular structure VLSI circuits, as well as circuits designed from standard cell libraries. Timing models for both logic gate and transmission gate circuit forms are developed. For logic gates, output transition time and delay time are functions of input transition time and load impedance. Effective resistances for conducting transmission gates and switching transmission gates are functions of input transition time and load capacitance. Transmission gate circuits are then modeled as equivalent RC circuits. Separate waveform models and delay calculation methods exist for both types of circuit forms, with an interface to enable the use of both methods in the same simulation. An experimental event-driven simulator was developed to test the accuracy of the macromodels and to estimate improvements in execution time with respect to SPICE. Typical delay times were within 5% for logic gate circuits and 10% for transmission gate circuits when compared with SPICE. The execution time of the experimental simulator was over two orders of magnitude faster than SPICE.

A bst ractThis paper describes EXCL, an automated circuit extraction program that transforms an IC layout into a circuit representation suitable for detailed circuit simulation. The program has built-in, general extraction algorithms capable of accurate computations of intercopnection resistance, internodal capacitance, ground capacitance, and transistor sizes. However, where possible, the general algorithms are replaced with simple techniques, thereby improving execution speed. A basic component of the extractor is a procedure that decomposes regions into domains appropriate for specialized or simple algorithms. The paper describes the decomposition algorithm, the extraction algorithms and discusse.~ how they connect with the rest of EXCL.

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These experiments suggest that hydrolysis to HF cannot solely explain COF toxicity. Although HF and COF may have common injury mechanisms, they are expressed to markedly different degrees and temporal occurrence.