| 摘要 |
An apparatus and method inhibit failure of a transistor, such as a switching transistor, due to short circuiting of a load connected thereto. Sensing is doneperiodically for short circuits of the load and a signal to the controlling element of the transistor is curtailed when a short circuit is sensed. Current through the transistor is limited sufficiently to prevent failure of the transistor between the periodic sensing for short circuits. The periodic sensing may be done by a digital processor. The limitation of current through the transistor may be accomplished by a second transistor connected to the base of the output transistor which you switched on to starve current directed flowing in the controlling element of the transistor when the current through the transistor is at least as great as a pre-set amount. Alternatively, where a FET is used as the switching transistor, the limitation of current may be accomplished by limiting the voltage applied to the gate terminal.
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