RTD-based reconfigurable logic gates for programmable logic array applications

Resonant-tunneling-diode (RTD) based reconfigurable logic gates have been designed and fabricated for RTD-based programmable logic array (PLA) applications. As PLA building blocks, two reconfigurable logic gates with three input terminals are proposed. The implemented gates show the reconfigurable functions of AND, OR, Majority, NOT, XOR, XNOR and 3-input XOR exploiting threshold characteristics of the RTD monostable-bistable transition logic element (MOBILE). The operation of the fabricated gates is successfully confirmed up to the clock frequency of 5 GHz. As for the full-adder topology, the number of devices in the proposed gate-based full-adder is less than a half of that in the conventional CMOS full-adder topology.