Ultralinear negative resistance using two complementary junction transistors

Two new negative-resistance circuits based on a pnp¿npn analogue of a pnpn structure are described. Both offer ultralinear, although asymmetric, regions of negative resistance. Analytical equations describing both the voltage-controlled and current-controlled i/v characteristics are given. For an ideal transistor the dynamic input resistance for both configurations is equal to the negative of the load resistance.