An Efficient Single-Layer Crossing Based 4-Bit Shift Register Using QCA

摘要

In co-planar QCA fabrication, QCA wire crossing is a challenging task as defects appear to be inherent due to two cell types in single layout structure. In this paper, a compact 2:1 multiplexer is presented which occupies a minimum area in QCA technology. This work also showcases a successful implementation and simulation of 4:1 multiplexer, level trigger D flip-flop and 4-bit shift register using QCADesigner tool. The 4:1 multiplexer and shift register are more robust and enjoy single-layer wire crossing, which requires only one type of cells. The comparison results show superiority of the proposed designs over the previous designs in terms of complexity and delay.