New ECCII-based electronically controllable current-mode instrumentation amplifier with high frequency performance

In this paper, a new electronically controllable current-mode instrumentation amplifier (CMIA) is presented. The proposed CMIA is based on only two electronically tunable second-generation current conveyors (ECCIIs). It does not need any passive element which makes it highly suitable for integration. More interestingly, high CMRR is achieved without the need for matching between active elements. Its input and output signals are current and it enjoys low input and high output impedances, respectively. Due to the inefficiency of the existing ECCIIs, a new ECCII circuit is also designed to be used in the proposed CMIA structure. PSPICE simulation results using 0.18μm TSMC CMOS technology and supply voltage of ±0.9V, shows CMRR of 42dB and fixed -3dB bandwidth of 68MHz for differential-mode gain ranging from 0dB to 27dB.