In order to compare the influence of process–voltage–temperature (PVT) variations on the LCFFs, these LCFFs are simulated through different process corners, voltage and temperature. The results are shown in Fig. 10. It is obvious that the proposed DBS-LCFFCC gains power improvements in all five corners, while the proposed DBS-LCFFP gains delay improvements in all five corners. Moreover, the simulation results also show that the proposed DBS-LCFFCC has the lowest power dissipation as compared with others at different PVT variations, while the proposed DBS-LCFFP has the lowest delay as compared with others at different PVT variations.