Negative resistance devices: Part II

Abstract As a sequel to Reference 1, this paper presents new analytical and topological guidelines for synthesizing negative‐ resistance devices. Among other things, these guidelines can be used to tune the devices by varying the magnitude and dynamic range of the negative (small‐signal) resistance. Necessary and sufficient conditions are given for a circuit containing only one bipolar transistor and linear reciprocal passive two‐ports (e.g. ideal transformers) to exhibit a negative resistance. In the special case where the circuit contains only one ideal transformer, one transistor and linear positive 2‐terminal resistors, an equivalent topological criterion which can be checked by inspection is given. Finally, three canonical negative‐resistance one‐ports containing two identical bipolar transistors, linear positive 2‐terminal resistors and batteries are synthesized to exhibit an odd‐symmetric (hence active) voltage‐controlled or current‐controlled v‐i curve.