Piezoelectric microphones

• US 20080101625A1
• Filed: 10/27/2006
• Published: 05/01/2008
• Est. Priority Date: 10/27/2006
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Inventors: Goel, Atul, Fazzio, R. Shane
• Granted Patent: US 8,369,555 B2
• Time in Patent Office: Days
• US Class Current: 381/92
• CPC Class Codes: H04R 17/02 Microphones
• CPC Class Codes: H04R 19/005 using semiconductor materials
• CPC Class Codes: H04R 19/016 for microphones
• CPC Class Codes: H04R 2410/05 Noise reduction with a separate noise microphone
• CPC Class Codes: H04R 2499/11 Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407
• CPC Class Codes: H04R 3/04 for correcting frequency response
• CPC Class Codes: H04R 31/00 Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor manufacture of microstructural arrangements of deformable or non-deformable structures in general B81C1/00182

Abstract

Electronic devices and microphone devices are described.

Claims

1. An electronic device, comprising:

a first microphone operative to receive audio signals from a first direction;

a second microphone operative to receive audio signals from a second direction; and

a controller operative to engage selectively the second microphone to receive ambient audio noise or to receive an audio input.

2. An electronic device as claimed in claim 1, further comprising a microprocessor adapted to receive an output signal from the second microphone and operative to provide noise cancellation to an output signal of the first microphone.

3. An electronic device as claimed in claim 1, wherein the controller is adapted to receive an output signal from the second microphone and operative to provide noise cancellation to an output signal of the first microphone.

4. An electronic device as claimed in claim 1, wherein the electronic device comprises one or more of:

a mobile phone;

a portable digital assistant (PDA);

a portable video recorder;

a portable music recorder;

a portable voice recorder;

a portable camera;

a computer;

a remote control;

a tablet computer;

a sound recording device and a laptop computer.

5. An electronic device as claimed in claim 1, wherein the audio input is an audio portion of an audio/video signal.

6. An electronic device as claimed in claim 1, wherein the first microphone is adapted to receive a voice input.

7. An electronic device as claimed in claim 1, further comprising at least one additional microphone, which is adapted to receive ambient audio noise or to receive an audio input, or both.

8. An electronic device as claimed in claim 1, wherein at least one of the microphones is a piezoelectric microphone.

9. An electronic device as claimed in claim 1, wherein the first microphone comprises a first film bulk acoustic (FBA) structure and the second microphone comprises a second FBA structure.

10. A microphone device, comprising:

a first microphone disposed over a substrate and adapted to receive audio signals from a first direction; and

a second microphone disposed over the substrate and adapted to receive audio signals from a second direction.

11. A microphone device as claimed in claim 10, wherein the first microphone comprises a first film bulk acoustic (FBA) structure and the second microphone comprises a second FBA structure.

12. A microphone device as claimed in claim 10, further comprising at least a third microphone.

13. A microphone device as claimed in claim 10, wherein the second microphone is adapted to receive audio signals from the first direction.

14. A microphone device as claimed in claim 10, wherein the audio signals from the first direction are speech signals and the audio signals from the second direction are ambient noise signals.

15. A microphone device as claimed in claim 14, wherein the ambient noise signals are used to provide noise cancellation to an output signal of the first microphone.

16. A microphone device as claimed in claim 10, wherein the audio signals from the first and second directions are speech signals.

17. A microphone device as claimed in claim 10, wherein the substrate is disposed in a package.

18. A microphone device as claimed in claim 17, wherein the package further comprises an acoustic barrier disposed between the first and the second microphones.

19. A microphone device as claimed in claim 17, wherein the package includes a first sound input adapted to receive the audio signals from the first direction and a second sound input adapted to receive the audio signals from the second direction.

20. A microphone device as claimed in claim 10, further comprising a cap structure over the second microphone, wherein the cap structure substantially isolates the second microphone from audio signals from the first direction.

21. A microphone device, comprising:

a first microphone comprising a first film bulk acoustic (FBA) device, wherein the first microphone is adapted to receive audio signals from a first direction; and

a second microphone comprising a second FBA device, wherein the second microphone device is adapted to receive audio signals from a second direction.

22. A microphone device as claimed in claim 21, further comprising at least a third microphone comprising a third FBA device.

23. A microphone device as claimed in claim 21, wherein the second microphone is adapted to receive audio signals from the first direction.

24. A microphone device as claimed in claim 21, wherein the audio signals from the first direction are voice signals and the audio signals from the second direction are ambient audio noise signals.

25. A microphone device as claimed in claim 21, wherein the audio signals from the first and second directions are voice signals.

26. A microphone device as claimed in claim 21, wherein the first mic is disposed over a first substrate, and the second mic is disposed over a second substrate.