A current threshold detector circuit.

摘要

A detector circuit (10) responsive to a current supplied to an input (14) thereof provides an output signal when the magnitude of the current exceeds a predetermined threshold level includes a multi-collector transistor (12) having a first one of its collectors connected to the base thereof and an emitter coupled to the input. A diode (16) formed by a diode-connected transistor is coupled to the first collector of the multi-collector transistor. A second transistor (20) is provided having its collector coupled to the second collector of the multi-collector transistor, a base coupled to the first collector and an emitter which is coupled to a pair of series connected resistors. The second transistor is operated at a lower current density than the diode- connected transistor such that the former operates in a saturated condition until such time that the input current exceeds the threshold level to produce the output signal. <IMAGE>