Electronically tunable memristor emulator circuit

In this paper, memristor emulator circuit which is built with off the shelf electronic devices is presented. It consists of three operational transconductance amplifiers (OTA) and four second generation current conveyors (CCII). Using OTA offers an extra control parameter, operational transconductance parameter (gm), in addition to frequency (f) and amplitude value of voltage across emulator (vm). Since gm is proportional to current flowing through the bias terminal of OTA, it is possible to change the memristance variation via a simple change of amplitude value. Since gm parameter is adjustable via an external dc voltage/current source, the memristance of presented emulator circuit is electronically tuneable. Mathematical model is derived to characterize the behaviour of the emulator circuit. Frequency analysis is performed to determine how to maintain the pinched hysteresis loop at high frequencies. The presented emulator circuit is simulated with SPICE simulation program. The breadboard experiment of emulator circuit is built using CA3080 and AD844 ICs for OTA and CCII devices respectively. Frequency dependent pinched hysteresis loop in the current versus voltage plane holds up to 10 kHz. Mathematical model and theoretical analyses show a good agreement with SPICE simulation and experimental test results.