In a synchronous digital circuit, the longest path between two flip-flops has a combinational logic delay of 800 ps. The flip-flops have a clock-to-Q delay of 100 ps, a setup time of 50 ps, and a hold time of 30 ps. Ignoring clock skew and jitter, what is the maximum possible clock frequency for this circuit?
To find the maximum clock frequency, calculate the minimum clock period (Tmin) required to satisfy the setup time constraint:
Data must launch from the first flip-flop, pass through the combinational logic, and settle before the next clock edge.
Tmin = Tc2q + Tlogic + Tsetup
Tmin = 100ps + 800ps + 50ps = 950psFmax = 1/Tmin
Fmax = 1/950*(10^12) =~ 1.053 Ghz