| 摘要 |
<p>An optically coupled switch suited for use in opto-isolators is described. A field effect transistor(FET) that need itself not be photosensitive is used and the control voltage, i.e., the gain-source voltage, which controls the amount of current flowing through the FET, is developed by a series connected photodiode array having at least one photodiode and which is connected between the gate and source of the FET controls the current through the FET. A symmetric optically coupled bilateral switch is obtained by using two series connected photodiode arrays. The first array is connected between the gate and source and the second is connected between the gate and drain of the FET, respectively. The operation of the bilateral switch is independent of the polarity of the voltage across the FET and does not require an external voltage source to establish a bias between gate and source or gate and drain.</p> |
