Noise margins of threshold logic gates containing resonant tunneling diodes

Threshold gates consisting of resonant tunneling diodes (RTDs) in conjunction with HBTs or CHFETs or MOSFETs can form extremely compact, ultrafast, digital logic alternatives, and may be used for digital signal processing applications in the near future. The resonant tunneling phenomenon causes these circuits to exhibit super-high-speed switching capabilities. Additionally, by virtue of being threshold logic gates, they are guaranteed to be more compact than traditional digital logic circuits, while achieving the same functionality. However, reliable logic design with these gates will need a thorough understanding of their noise performance and power dissipation among other things. In this brief, we present an analytical study of the noise performance of these threshold gates supplemented by computer simulation results, with the objective of obtaining reliable circuit design guidelines.