| 摘要 |
PURPOSE:To prevent break-down of a transistor(TR) by clamping a base input voltage to a prescribed constant voltage by a clamp circuit or a reference voltage generating circuit when an abnormal external voltage is inputted to a base input of the TR in error. CONSTITUTION:When a voltage inputted to a base of a TR Q1 is within a conventional voltage range, a prescribed normal operation is attained. That is, when a voltage higher than a constant voltage +VBE is inputted due to any cause, the base input voltage is suppressed to (constant voltage - clamp voltage) by the clamp circuit 1. As a result, the base-emitter voltage of the TR Q, is suppressed below the break-down voltage. |
