| 摘要 |
<p>PURPOSE:To contrive the improvement in the dv/dt resistivity and noise resistivity without deterioration of sensitivity for the subject semiconductor device by a method wherein a depletion type FET is connected in between the gate and cathode on an SCR, and light-emitting and light receiving elements are provided between a gate and a source. CONSTITUTION:The light-emitting elements 3 and 10 do not function while no signal is existed between terminals 2a and 2b, the status between a drain and a source is turned to low resistive when the gate potential of an FET8 is at zero and the SCR1 is not erroneously turned on by dv/dt and noises. When a signal is inputted in between the terminals 2a and 2b, elements 3 and 10 emit light, the SCR and a photo electromotive force element 9 receive photo beam energy, an element 9 negatively biases between a gate and a source of the FET8, and the FET8 is turned to OFF when pinch-OFF voltage is exceeded. Accordingly, the short-circuit condition between the gate and cathode is cancelled and turned to ON by the ignition energy sent from the element 3. At this time, the impedance between the terminals 1a and 1b on SCR has sufficiently been increased and no ignition energy is deteriorated.</p> |
