The described embodiments relate to the general area of Field Programmable Gate Arrays (FPGAs), and, in particular, to the architecture and the structure of the building blocks of the FPGAs. Proposed logic units, as separate units or a chain of units, which are mainly comprised of look-up tables, multiplexers, and latches, implement different mathematical and logical functions. Having two outputs, the embodiments of the logic unit can operate in a split mode and perform two separate logic and/or arithmetic functions at the same time. Chains of the proposed logic units, wherein every other unit is clocked by one of the two half clock cycles and utilizes local interconnections instead of traditional routing channels, add to efficiency and speed, and reduce required real estate.