TUNABLE WAVEFORM GENERATORS USING SINGLE DUAL-CURRENT OUTPUT OTAs

Abstract

Two novel electronic-tunable waveform generators using a single dual-current output operational transconductance amplifier (DO-OTA) with a few passive components are proposed in this paper. The first one can produce symmetrical square and triangular waveforms simultaneously. Based on the first topology, an additional N-MOS is adopted as a switching element to construct the second proposed circuit, which can generate a pulse waveform by a negative triggering signal. The repetitive frequency and pulse width of the presented circuits are adjustable by external passive components. Moreover, the output levels of the proposed circuits can be controlled by the DO-OTA's bias currents. These waveform generators feature more compact configurations compared to the existing designs. Experimental results are close to the theoretical analyses.