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摘要

A device for protecting a push-pull output stage (Gv) against a short-circuit between the output terminal (A) and the positive pole (+Vcc) of the supply, comprising a first (A1) and a second (A2) threshold comparator, both having a first input terminal coupled to the output terminal (A) of the output stage and both having a second input terminal coupled to a predetermined voltage reference. The reference potential (RIF1) to which the threshold comparator (A1) is coupled is kept at a potential which is lower than the other reference potential (RIF2) to which threshold comparator (A2) is coupled. The output terminal of the first comparator (A2) is coupled to the activation terminal of a low impedance circuit means (LI) inserted between the output terminal (A) of the output stage and the negative pole (-Vcc) of the supply. The output terminal of the second comparator (A2) is coupled to an inhibitor terminal of the output power amplifier stage (Gv).