Title: Circuit utilizing open-base transistor as leakage bypass device

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Abstract: A floating base transistor connected within an integrated circuit to provide a high temperature high voltage low current bypass device having the same type of temperature dependence as the leakage current shunted therethrough. The bypass device is connected to provide its I.sub.CEO current as a current source through which a parasitic leakage current is diverted which would otherwise produce a base current of an output transistor which is supposed to be in the off condition. The parasitic leakage current includes the I.sub.CEO current of an opposite polarity driving transistor in the off condition having its emitter connected to a power supply and its base connected to an input circuit and its collector connected to the base of the output transistor. In one embodiment the floating base transistor is a PNP substrate transistor having its collector connected to ground, its emitter connected to the base of an NPN output transistor, and its base floating. The current of the floating base transistor is greater than the parasitic leakage current of a PNP driving transistor, so the NPN output transistor is held in the off position.


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