Abstract: A system which simplifies the clock tuning process for a clock buffer tree. Essentially, a clock buffer tree is provided where the clock buffer tree includes clock buffers of different strengths. The different strength clock buffers which are in the clock buffer tree have the same pin-out configuration. Hence, it is easy and straightforward to upsize or downsize any of the clock buffers in the clock buffer tree, and it is guaranteed that the new cell will fit into the old cell's slot in the tree. Since none of the nets need to be modified, consistent timing results are achieved. Moreover, the new timing for the modified clock buffer can be anticipated because its wire loading does not change at all. The ease of clock tuning makes it much easier to design clock buffer trees and layouts, and allows the overall design to be completed faster and easier.

Abstract: A clock gating cell and a method of manufacturing the same. In one embodiment, the clock gating cell includes: (1) gate signal and clock signal inputs configured to receive gate enable and clock input signals, respectively, and (2) a gated clock signal output configured to generate a gated clock signal that is a function of states of the gate enable and clock signals, the clock gating cell treated as an atomic entity in a cell library.