A New Bilateral Optoisolator Circuit

A simple optoisolator circuit is proposed which has bilateral transmission. It is composed of two optoisolators in a positive feedback arrangement without going into instability. The experimental and analytical results show that this circuit simulates not only the transmission gain or attenuation corresponding to the step-up or step-down transformer, but also the bilateral amplification. Other features, such as an impedance buffer, improvement of the frequency response, and high packaging density, are also achieved.