Process for driving a sensor with offset control

US6029497A · kind A · utility

Assignee

• Temic Telefunken Microelectronik · DE

Inventors

• Gerald Brinks · Burgrieden, DE
• Manfred Weinacht · Dettingen unter Teck, DE

Key dates

• Filing date: Mar 2, 1998
• Grant date: Feb 29, 2000
• Expiry date: Mar 2, 2018

Classification

• Technology area (CPC G): Physics
• CPC primary: G01P15/123
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The invention concerns a process for driving a sensor with offset control. Such processes for driving are required, for example, to be used in acceleration transducers in motor vehicles for triggering, e.g., airbags or belt-tensioning devices. However, with existing processes the output nominal signal was repeatedly corrupted, e.g., by temperature-related interference signals, also known as the offset. In addition, existing systems are unreliable during turn-on. However, with the process according to this invention, the sign and the value of the difference between the output signal and a reference voltage is detected at a fixed or variable time pulse, with the sign changing the measuring voltage at the output and the difference value determining the clock frequency for this control process. Also, during turn-on a significantly increased clock frequency will be reduced in stages until the operating frequency is reached. The process according to this invention, therefore, allows reliable and low cost acceleration transducers to be realized.