Single Active Element-Based Tunable Square/Triangular Wave Generator with Grounded Passive Components

This paper presents a novel circuit of tunable square/triangular wave generator based on single active element and grounded passive components. The structure of the proposed generator is simple as it consists of one multiple-output differential voltage current conveyor transconductance amplifier (MO-DVCCTA) as active element and one grounded resistor and one grounded capacitor as passive components. The proposed generator provides triangular wave in voltage mode and square wave in both voltage mode and current mode simultaneously. The proposed generator enjoys the features of availability of square wave in both current mode and voltage mode, electronically tunable duty cycle via DC current over a 93-7% range, electronically and independently adjustable DC level of voltage-mode square wave and triangular wave via an additional DC current, independent and electronic control of amplitude of current-mode square wave by bias current and independent tunability of oscillation frequency by grounded capacitor. Moreover, the operation of the proposed generator at 50% duty cycle exhibits the electronic and independent control of oscillation frequency via bias current also. As an additional feature, the proposed generator exhibits < 1% nonlinearity up to a frequency of 123.9 kHz. The maximum temperature coefficient of oscillation frequency over a temperature range of 0-50 C is found 185 ppm/C which is quite good in view of temperature stability of the oscillation frequency. The prototype of MO-DVCCTA based on commercial ICs has been used in the realization of circuit of the proposed generator. The PSPICE simulation results and experimental results are given to validate the proposed generator.