| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a semiconductor switch capable of increasing energy efficiency. <P>SOLUTION: A semiconductor switch 1 drives an LED 2 by a driving circuit 3 to cause the LED 2 to emit light. The light emitted from the LED 2 is received by a light-receiving unit 4. The driving circuit 3 includes a bipolar transistor 31, a coil 32, and a diode 33 and the like. The bipolar transistor 31 is switched to a conductive state and a non-conductive state. When the bipolar transistor 31 is in the conductive state, current is supplied from a power supply to the LED 2. When the bipolar transistor 31 is in the non-conductive state, current is not supplied from the power supply to the LED 2. The coil 32 is connected in series to the LED 2. When the bipolar transistor 31 switches from the conductive state to the non-conductive state, the coil 32 produces an induced electromotive force due to a self-induced action. The diode 33 is connected in parallel to the LED 2 and the coil 32. When the bipolar transistor 31 is in the non-conductive state, the diode 33 recycles current to the LED 2 by the induced electromotive force produced by the coil 32. <P>COPYRIGHT: (C)2013,JPO&INPIT |
