Sensor element for a pressure sensor

Patent metadata

Field	Value
Publication number	US-10670482-B2
Application number	US-201615775253-A
Country	US
Kind code	B2
Filing date	Oct 14, 2016
Priority date	Nov 18, 2015
Publication date	Jun 2, 2020
Grant date	Jun 2, 2020

Abstract

A sensor element for a pressure sensor, includes a sensor membrane on which a defined number of piezoresistors are situated, the piezoresistors being configured in a circuit in such a way that, when there is a change in pressure an electrical change in voltage can be generated; at least two temperature measuring elements configured in relation to the sensor membrane in such a way that temperatures of the sensor membrane at positions of the piezoresistors can be measured using the temperature measuring elements, an electrical voltage present at the circuit of the piezoresistors due to a temperature gradient being capable of being compensated computationally using the measured temperatures.

First claim

What is claimed is:

1. A sensor element for a pressure sensor, comprising:
a sensor membrane;
a plurality of piezoresistors situated on the sensor membrane and configured in a bridge circuit such that a change in pressure causes an electrical change in voltage; and
a plurality of temperature measuring elements configured in relation to the sensor membrane so that temperatures of the sensor membrane at respective positions of the piezoresistors are measurable using the temperature measuring elements;
wherein the sensor element is configured to determine a temperature gradient over the sensor membrane based on output of the temperature measuring elements and, based on the determined temperature gradient, computationally compensate for a deviation of an electrical bridge voltage of the bridge circuit that is present due to the temperature gradient,
wherein a number of the piezoresistors and the temperature measuring elements is the same, and
wherein the temperature measuring elements are situated on the sensor membrane with an angled orientation to side segments of the sensor membrane, so as to minimize a sensitivity to pressure.

2. The sensor element as of claim 1 , wherein at least one of the temperature measuring elements is situated on the sensor membrane.

3. The sensor element of claim 1 , wherein at least one of the temperature measuring elements is situated adjacent to the sensor membrane.

4. The sensor element of claim 1 , wherein at least one of the temperature measuring elements is situated at each of a plurality of corner regions of the sensor membrane.

5. The sensor element of claim 4 , wherein a respective one of the temperature measuring elements is situated at a defined distance from each of the piezoresistors.

6. The sensor element of claim 1 , wherein the temperature gradient is a curved line, and wherein the temperature measuring elements are situated along the curved line of the temperature gradient.

7. The sensor element of claim 1 , wherein the temperature measuring elements include temperature-sensitive diodes.

8. The sensor element of claim 1 , wherein the temperature measuring elements include temperature-sensitive resistors.

9. A method for producing a sensor element for a pressure sensor, the method comprising:
arranging a plurality of piezoresistors on a sensor membrane in a bridge circuit such that a change in pressure causes an electrical change in voltage; and
arranging a plurality of temperature measuring elements relative to the sensor membrane so that temperatures of the sensor membrane at respective positions of the piezoresistors are measurable using the temperature measuring elements;
wherein the sensor element is configured to determine a temperature gradient over the sensor membrane based on output of the temperature measuring elements and, based on the determined temperature gradient, computationally compensate for a deviation of an electrical bridge voltage of the bridge circuit that is present due to the temperature gradient,
wherein a number of the piezoresistors and the temperature measuring elements is the same, and
wherein the temperature measuring elements are situated on the sensor membrane with an angled orientation to side segments of the sensor membrane, so as to minimize a sensitivity to pressure.

10. The method of claim 9 , wherein the temperature measuring elements include temperature-sensitive diodes or temperature-sensitive resistors.

11. The method of claim 9 , wherein the temperature measuring elements are situated on the sensor membrane or adjacent to the sensor membrane such that temperatures can be measured at positions of the piezoresistors using the temperature measuring elements.

12. The method of claim 9 , wherein the angled orientation has an angle of about 45 degrees.

13. The sensor element of claim 9 , wherein the angled orientation has an angle of about 45 degrees.

Assignees

• Bosch Gmbh Robert

Inventors

• Zehringer Stefan
• Lestyan Zoltan
• Fix Richard
• Franz Jochen
• Mitschke Michaela
• Frey Tobias Sebastian

Classifications

• G01L19/0092 Primary

  Pressure sensor associated with other sensors, e.g. for measuring acceleration or temperature (G01L9/025, G01L9/045, G01L9/065, G01L9/085, G01L9/105, G01L9/125, G01L19/02, G01L19/04 take precedence; measuring two or more variable G01D21/02; temperature sensors with pressure compensation G01K1/26) · CPC title

• G01L9/085 Primary

  with temperature compensating means (non electric temperature compensating means G01L19/04) · CPC title

• G01L9/0052 Primary

  of piezoresistive elements (circuits therefor G01L9/06) · CPC title