A four-bit ALU chip based on a metal gate PMOS process and 10-urn minimum geometries was designed. The operations performed by the ALU included ADD w/carry, SUBTRACT(2’s complement), INCREMENT, DECREMENT, and the logic functions AND, OR, XOR, and COMPLEMENT. Due to space limitations no data or shift registers were included on the chip. PMOS NOR gates and inverters were used in the hardware Implementation of the logic design. The ALU chip was laid out by using the ICE (Integrated Circuit Editor) design tool.
Bonaker, John F.
"Design of a Four-Bit Microprocessor A.L.U Using PMOS 10-um Metal Gate Technology,"
Journal of the Microelectronic Engineering Conference: Vol. 2
, Article 3.
Available at: http://scholarworks.rit.edu/ritamec/vol2/iss1/3