Patent · US Expired

Threshold detection circuit

US5111071A · kind A · utility

12Cited by
4References
28Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 3, 1991
Grant dateMay 5, 1992
Priority date
Expiry dateApr 3, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R19/16576
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A threshold detection circuit (10) is provided which comprises an input node (12) and an output node (14). The input node (12) is coupled to a current mirror (22) through a resistor (32). The current mirror (22) is further coupled to another current mirror (16), which is arranged to receive a reference current proportional to absolute temperature. The reference current is mirrored and, having been increased by a multiplier is received by a current sink (28). When the voltage level at the input node (12) exceeds a predetermined voltage threshold level, the current exceeding the amount sinkable by the current sink (28) is directed to the base of a switching transistor (30) coupled to the output node (14), and produces an output voltage level at the output node (14) indicative of the threshold voltage level being reached an/or exceeded at the input node (12). The predetermined threshold voltage may be at a level exceeding the circuit supply voltage level and is independent of ambient operating temperature.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.