A four bit serial adder was designed with PMOS NOR gates from a truth table that models binary serial addition. Three storaqe reqisters were also included in the desiqn, two-four bit shift registers for the incoming digits and one-five bit register for the sum. A simple five gate latch was used for the bits of these registers. The circuit was layed out using ICE , a software program designed to facilitate circuit layout for mask making at R.I.T.
Macaluso, Steven M.
"Design, Layout and Realization of an All NOR Enhancement Type PMOS Serial Adder,"
Journal of the Microelectronic Engineering Conference: Vol. 1:
1, Article 17.
Available at: https://repository.rit.edu/ritamec/vol1/iss1/17