CIRCUIT PROTECTION DEVICES

摘要

The present invention provides a circuit protection device that has a reduced size and weight and is particularly suitable for use, for example, in portable electronic devices and high density electronic circuits. According to one embodiment of the present invention, a circuit protection device comprises a positive coefficient temperature (PTC) element and a bipolar transistor having base, collector, and emitter terminals. The PTC element is connected between the base and collector terminals of the transistor. The PTC element may be thermally coupled to the transistor and packaged with the transistor as a hybrid device. An electrical load may be connected to the collector terminal of the transistor. According to another embodiment of the present invention, a circuit protection device comprises a PTC element and a Darlington circuit (12) having base, collector and emitter terminals. The PTC element is connected between the base and collector terminals of the Darlington circuit. The PTC element may be thermally coupled to the Darlington circuit and packaged with the Darlington circuit as a hybrid device. An electrical load may be connected to the collector terminal of the Darlington circuit. The Darlington circuit may also be a complementary Darlington circuit (22).