A critical timing path within a GPU core has the following worst-case parameters: T_cq(max) = 0.6 ns, T_comb(max) = 1.4 ns, and T_setup = 0.4 ns. Due to asymmetric routing, the clock tree has a positive skew of 0.4 ns (meaning the capture clock edge physically arrives 0.4 ns later than the launch clock edge). What is the absolute maximum clock frequency (F_max) at which this path can reliably operate?
The minimum clock period (T_min) required to satisfy setup time is: T_min = T_cq(max) + T_comb(max) + T_setup - Skew T_min = 0.6 + 1.4 + 0.4 - 0.4 = 2.0 ns. Positive skew helps setup time by pushing the capture edge out further, reducing the required clock period. F_max = 1 / T_min = 1 / (2.0 10^-9 s) = 500 10^6 Hz = 500 MHz.
