| 摘要 |
An optically sensitive switch, e.g. for use in an opto-isolator, comprises a FET (3) exemplified by an n-channel depletion mode device, gate voltage being provided by photovoltaic means (7) exemplified by an array of photodiodes connected in series. The switch may be turned on or (as in the example) off by illuminating the photovoltaic means, no other power source being required. By including a similar photovoltaic means between drain and gate, with reverse polarity blocking diodes in series with each of the photovoltaic means, a bilateral switch may be provided. A further level of control may be obtained by using a photo-FET as the FET. <IMAGE> |
