Circuit for detecting the threshold of the supply voltage Vcc with little dependence on temperature and on variations in technological parameters

摘要

The high threshold detector comprises an least one inverter I at the output of a resistive divider (Dr). In a first embodiment, the latter comprises in a first branch an N-channel MOS transistor Tn2 for compensation of an N-channel MOS transistor Tn1 in a second branch of the divider (Dr). In a second embodiment, the second branch also includes a P-channel MOS transistor Tp2 for compensation of the channel transistor Tp1 in the first branch. The two P-channel (respectively N-channel) transistors have the same technological characteristics and operate in the same resistive mode. The detector may be used over a wide range of temperatures of the circuit into which it is integrated (-40 DEG to +85 DEG C) without significantly perturbing the switching voltage of the detector corresponding to the detection of the high threshold of the supply Vcc. <IMAGE>