| 摘要 |
PURPOSE:To required only one current source and to reduce the mount volume of a semiconductor switch circuit by adopting the circuit constitution such that OFF driving is always applied while a current source is cut off and the OFF driving is released as soon as the current source is active. CONSTITUTION:A thyristor 1 keeps the OFF state because a P gate and a cathode are short-circuited by a 1st NPN transistor(TR) 2 when a current source 6 is inactive even if the leading edge of a voltage applied to the thyristor 1 is steep. When the current source 6 is active, the current from the current source 6 to the P gate of the thyristor 1 is not branched to the collector of a 1st NPN TR 2 and the thyristor 1 is turned on. Then the ON/OFF control is attained by employing the current source 6 to reduce the mount volume of the entire circuit. |
