Temperature detector on an integrated circuit

Abstract

An integrated circuit including a temperature threshold detector. This detector includes two MOS transistors with a same type of conductivity, circuitry for applying to the second transistor a gate-source voltage higher than the gate-source voltage of the first transistor by a value Vbe, VbE being the drop in voltage at the terminals of a forward-biased PN junction, and a comparator for comparing the currents flowing in the two transistors. The current in the second transistor diminishes faster than the current in the first transistor. If the dimensions of the transistors are accurately chosen, the curves pertaining to the diminishing of current (or curves deduced from these curves by homothetic transformation) intersect one another for a certain temperature. The detection of equality of the currents therefore enables a detection of the passage through this temperature.

Dependencies are inferred from the claim text.