Influence of transistor packages and circuit dimensions for accurate design of negative impedance converters

Negative impedance converters (NICs), which can produce negative capacitances or negative inductances, are quite attractive for their potential for developing a new type of circuits we have never designed so far. However, those circuits, composed of active devices such as transistors or operational amplifiers, can easily become unstable due to their non-linearity, undesired couplings and excessive loop gains. Therefore, accurate circuit design is strongly requested. This paper theoretically studies the influence of transistor packages and circuit dimensions on NIC circuits, in collaboration with a circuit simulator Ansys Designer and a full-wave EM simulator Ansys HFSS.