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4 I/P OR gates designed with large (v0 version), medium (v3 version) and small (v4 version) input stages. The stage effort is 1.9 for the or4v0x05, 2.2 for the or4v0x1, 2.6 for the or4v0x2, 3.3 for the or4v3x2, 2.8 for the or4v0x3 and 4.0 for the or4v4x05. The v0 cells are optimised for speed with typical wireload values, while the v4 cell is optimised for a zero wireload capacitance. The v3 is designed to have a low Prop delay and high drive but still be small by using an unfolded input NOR gate. The P/N ratio is kept to about 2 except for the or4v3x2 NOR gate which has a P/N ratio of about 1. |