Patent · US Expired

On-chip temperature sensing system

US5639163A · kind A · utility

49Cited by
16References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 14, 1994
Grant dateJun 17, 1997
Priority date
Expiry dateNov 14, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01K7/01
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A pair of on-chip thermal sensing diodes are formed together and interconnected with a common cathode to form a differential sensing pair. A pair of precision resistors external to the chip generates two constant currents, one for each diode, with a ratio of one to the other on the order of 100 to 1. The precision resistor values are selected so that variations about the nominal values of metal and via resistances between the diode contacts and the chip contact pads (e.g. C4 contacts) are negligible compared to the precision resistor values. Leads, connected respectively to two pads on the chip, couple a differential output of the anode voltages of the diode pair to the input of a high impedance amplifier.

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