| 摘要 |
PROBLEM TO BE SOLVED: To surely prevent the element from being destructed even when the dispersion of characteristics is present in a photo triac coupler and to perform phase control with inexpensive constitution. SOLUTION: A serial circuit composed by serially connecting a pair of surge absorbers SA1 and SA2 is connected parallelly to output terminals OUT1 and OUT2 and short circuit connection is performed between the connection intermediate point (b) of both surge absorbers SA1 and SA2 and the connection intermediate point (a) of respective photo triacs TR1 and TR2 for constituting the two photo triac couplers PHT1 and PHT2. |
