摘要

In this study, a new versatile active element, namely multifunction current differencing cascaded transconductance amplifier (MCDCTA) is proposed. The proposed MCDCTA enjoys the advantages of low voltage, low-input and high-output impedance, wide bandwidth etc., and it simplifies the design of the current-mode analog signal processing circuit greatly, especially the design of high-order filter and oscillator circuits. Moreover, an example, a new current-mode multiphase sinusoidal oscillator (MSO) using the proposed MCDCTA is described in this paper. The proposed MSO consists only one MCDCTA and minimum grounded passive elements, it could provide 2n (n a parts per thousand 2) output current signals with equally phase difference, and the output current signals are all at high output impedance terminals. The oscillation condition and the oscillation frequency of the MSO could be linearly and electronically adjusted by controlling the bias currents of MCDCTA, and it is suitable for variable frequency oscillator application. The operation of the proposed oscillator has been verified through PSPICE simulation and experimental results.