Circuit configuration for compensating the temperature non-linearity of the characteristic curves of the piezoresistive measuring resistors connected in a bridge circuit

US6559661B1 · kind B1 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Joerg Muchow · Reutlingen, DE
• Joachim Horn · Treysa, DE
• Oliver Schatz · Reutlingen, DE

Key dates

• Filing date: Jul 18, 2001
• Grant date: May 6, 2003
• Expiry date: Jul 18, 2021

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S323/907
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A circuit arrangement is described for compensating temperature non-linearity of the characteristics of piezoresistive, metallic or polycrystalline resistors (bridge resistors) connected in a bridge circuit, the non-linearities being caused by non-linearities of the resistors, in particular due to the physical quantities affecting the bridge circuit (temperature, pressure, bimetal effects, non-linear membrane stresses), and the resistors being composed of partial resistors having different temperature coefficients, with each of the partial resistors having a certain linear and non-linear temperature response. The partial resistors of each bridge resistor are selected on the basis of their known linear and non-linear temperature characteristics so that an asymmetric layout of the bridge circuit is obtained and a non-linear variation of a bridge output voltage of the circuit arrangement can be essentially compensated.