Scaling of serially-connected MOS transistors with constant area constraint

Transistor channel width tapering in serially connected MOSFET chains decreases propagation delay and fall times, and reduces the power dissipation. Tapering is the process of changing the size of each transistor width within the serial chain, such that the largest transistor is connected to the power supply rail and the smallest transistor is connected to the output node. Analytical approaches are used to determine the optimal tapering factor for the serially connected MOSFET chain. Under a constant area constraint, the area gained from unscaled transistor widths is reallocated to the transistors using empirical approaches such that the overall delay is improved.