Pressure sensor for measuring pressure in an internal combustion engine

US5606117A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Manfred Vogel · Ditzingen, DE
• Werner Herden · Gerlingen, DE
• Jiri Marek · Reutlingen, DE
• Kurt Weiblen · Metzingen, DE

Key dates

• Filing date: Dec 16, 1994
• Grant date: Feb 25, 1997
• Expiry date: Dec 16, 2014

Classification

• Technology area (CPC G): Physics
• CPC primary: G01L23/18
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The pressure sensor for a combustion chamber includes a housing; a membrane closing the housing on its combustion chamber side; a monocrystalline silicon chip inside the housing and including a sensor circuit device provided with a bridge circuit device including a piezoresistor producing an electrical signal in response to applied pressure and a plunger positioned between the membrane and the silicon chip to transmit a pressure in the combustion chamber to the piezoresistor. The bridge circuit device is connected to an amplifier circuit located on the silicon chip. The amplifier circuit includes amplifier resistors having resistance values determinative of the offset of the signal and sensor sensitivity. A network circuit for offset and sensitivity adjustments is provided on the silicon chip and includes four adjusting circuits for offset, sensor sensitivity, temperature compensation of offset and for temperature compensation of sensor sensitivity. Each adjusting circuit includes parallel-connected adjusting circuit branches each including an adjusting resistor and a semiconductor element in series. The adjusting circuit branches of respective adjusting circuits are connected in p…