What is clock tree synthesis (CTS)?

Clock tree synthesis builds the clock distribution network from clock source to all sequential elements (flip-flops). Goals: minimize skew (variation in clock arrival times), achieve target latency, meet transition time constraints, and minimize power. CTS inserts clock buffers and inverters in a tree or mesh structure. Balanced trees reduce skew; useful skew can improve timing. Modern CTS considers: OCV (on-chip variation), concurrent clock-data optimization, and multi-mode multi-corner (MMMC) analysis. CTS significantly impacts timing closure and power.