| 摘要 |
<P>PROBLEM TO BE SOLVED: To prolong the life of a photocoupler as compared with the life of a single light-emitting element or the period before accidental failure of a single light-emitting element. <P>SOLUTION: The photocoupler comprises a first light-emitting element (first LED 1), a first power supply terminal 21 which supplies power to the first light-emitting element, a second light-emitting element (second LED 2), a second power supply terminal 22 which supplies power to the second light-emitting element, and a light-receiving element 6 arranged to face the first and second light-emitting elements. The photocoupler further includes a switch 30 which is inserted between the second power supply terminal 22 and the second light-emitting element and supplies power from the second power supply terminal 22 to the second light-emitting element when emission intensity of the first light-emitting element goes below a predetermined value. <P>COPYRIGHT: (C)2012,JPO&INPIT |
