Detector for rapid variations of the supply voltage of an integrated circuit.

摘要

The invention relates to integrated circuits and, more especially, to certain circuits requiring protection against malfunctioning due to variations in the supply voltage Vcc. …It is proposed that a detector of rapid variations in the supply voltage should be placed in the integrated circuit so as to interrupt or modify all or part of the functioning of the circuit in the event of a rapid variation in Vcc. The detector consists essentially of a capacitor (C) and a means of charging this capacitor by the supply voltage through a current limiter. The current limiter is a transistor (T3) connected as a diode (threshold voltage Vtn). A detection transistor (T1, T2) receives the relatively stable voltage from the capacitor on its gate and the voltage Vcc on its source. If Vcc varies abruptly, the detection transistor becomes conducting. The proposed assembly uses the difference between the threshold voltage Vtn of the current limiter and that (Vtp) of the detection transistor. ……