Patent · US Expired

Curvature correction of bipolar bandgap references

US4808908A · kind A · utility

51Cited by
8References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 16, 1988
Grant dateFeb 28, 1989
Priority date
Expiry dateFeb 16, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S323/907
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A bipolar bandgap reference circuit employing three resistors of selected nominal resistance values and a method of trimming the values of two of the resistors to cancel the slope and curvature of output voltage due to thermal drift. One of the resistors provides a positive temperature coefficient to counter the temperature dependency of bipolar base-emitter characteristics; this resistor is not trimmed. The other two resistors are thin-film, low TC devices and are "trimmed" (i.e., adjusted) sequentially, to match calculated values intended to minimize the first and second derivatives of the bandgap cell output, as a function of temperature.

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