LOW-COST MINIATURE MEMS VIBRATION SENSOR

• US 20170240418A1
• Filed: 12/16/2016
• Published: 08/24/2017
• Est. Priority Date: 02/18/2016
• Status: Abandoned Application

• Current Assignee: Knowles Electronics Llc (Knowles Corporation)
• Original Assignee: Knowles Electronics Llc (Knowles Corporation)
• Inventors: Qutub, Sarmad, Volk, Martin
• Application Number:
  US15/382,581
• Publication Number:
  US 20170240418A1
• Time in Patent Office: Days
• CPC Class Codes: B81B 2201/0285 Vibration sensors
• CPC Class Codes: B81B 7/0041 maintaining a controlled atmosphere with techniques not provided for in B81B7/0038
• CPC Class Codes: B81C 1/00269 Bonding of solid lids or wafers to the substrate
• CPC Class Codes: B81C 2203/0145 Hermetically sealing an opening in the lid
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H04R 1/021 incorporating only one transducer
• CPC Class Codes: H04R 1/04 Structural association of microphone with electric circuitry therefor in deaf-aid sets H04R25/00
• CPC Class Codes: H04R 19/04 Microphones H04R19/01 takes precedence
• CPC Class Codes: H04R 2201/003 Mems transducers or their use of the electrostatic type H04R19/005

Abstract

A vibrational sensor comprises a microelectromechanical (MEMS) microphone having a base and a lid defining an enclosure, a MEMS acoustic pressure sensor within the enclosure, and a port defining an opening through the enclosure and material that is arranged to plug the port of the MEMS microphone. In embodiments, the MEMS microphone further includes an integrated circuit within the enclosure that is electrically connected to the MEMS acoustic pressure sensor. In some embodiments, the integrated circuit is configured to bias and buffer the MEMS acoustic pressure sensor. In these and other embodiments, the integrated circuit includes circuitry for conditioning and processing electrical signals generated by the MEMS acoustic pressure sensor. In embodiments, the material is arranged with respect to the port so as to cause the MEMS acoustical pressure sensor to sense vibrational energy rather than acoustic energy as in a conventional MEMS microphone.

Claims

1. A vibrational sensor, comprising:

a microelectromechanical (MEMS) microphone having a base and a lid defining an enclosure, a MEMS acoustic pressure sensor within the enclosure, and a port defining an opening through the enclosure; and

material that is arranged to plug the port of the MEMS microphone.

2. The vibrational sensor of claim 1, wherein the material completely plugs the port.

3. The vibrational sensor of claim 2, wherein the opening in the enclosure defined by the port has a width, the material having a width that is greater than the width of the opening so as to completely cover the opening and thereby plug the port.

4. The vibrational sensor of claim 2, wherein the opening in the enclosure defined by the port has a width, the material completely filling the width of the opening.

5. The vibrational sensor of claim 2, wherein the opening in the enclosure defined by the port has a width, the material having a top portion with a width that is greater than the width of the opening, and a bottom portion that completely fills the width of the opening.

6. The vibrational sensor of claim 1, wherein the port defines the opening in the base of the MEMS microphone.

7. The vibrational sensor of claim 1, wherein the port defines the opening in the lid of the MEMS microphone.

8. The vibrational sensor of claim 1, wherein the material comprises an adhesive.

9. The vibrational sensor of claim 1, wherein the MEMS microphone further includes an integrated circuit within the enclosure that is electrically connected to the MEMS acoustic pressure sensor.

10. The vibrational sensor of claim 9, wherein the integrated circuit is configured to buffer the MEMS acoustic pressure sensor.

11. The vibrational sensor of claim 9, wherein the integrated circuit includes circuitry for conditioning and processing electrical signals generated by the MEMS acoustic pressure sensor.

12. The vibrational sensor of claim 11, wherein the conditioning and processing includes generating a digital PDM electrical output.

13. The vibrational sensor of claim 11, wherein the conditioning and processing includes generating a digital I2S electrical output.

14. The vibrational sensor of claim 11, wherein the conditioning and processing includes generating an analog differential electrical output.

15. The vibrational sensor of claim 11, wherein the conditioning and processing includes generating an electrical output is compatible with audio CODECs and/or digital signal processor (DSP) inputs.

16. The vibrational sensor of claim 1, wherein the material is arranged with respect to the port so as to cause the MEMS acoustical pressure sensor to sense vibrational energy rather than acoustic energy.

17. The vibrational sensor of claim 16, wherein the MEMS microphone is attached to a rear surface of a substrate.

18. The vibrational sensor of claim 17, wherein the material is arranged such that energy from vibrations from a front surface of the substrate propagate to the MEMS acoustic pressure sensor of the MEMS microphone.

19. The vibrational sensor of claim 1, further comprising a second port defining a second opening through the enclosure, and second material that is arranged to plug the second port of the MEMS microphone.