Power output stages with integrated logic for the detection of a load-current threshold are known in various embodiments. A typical application is in electronic ignition control devices for adjusting the dwell angle on automobile engines. Other types of current control for loads can also be developed with power output stages in which the reaching of the load-current threshold is indicated by the switching of an output transistor. In this case, it is also known to arrange this output transistor in an insulated .pi.-well. This arrangement, by itself or in combination with a connection resistor, does not, however, assure dependable operation of the output transistor, since with limited inverse current, -Ic, a maximum possible noise current can occur which no longer assures the maintenance of a blocked condition of the output transistor.
USPTO Backgrounds
USPTO Backgrounds