Piezoelectric mems device for producing a signal indicative of detection of an acoustic stimulus

Patent metadata

Field	Value
Publication number	US-12445782-B2
Application number	US-202318190719-A
Country	US
Kind code	B2
Filing date	Mar 27, 2023
Priority date	Feb 29, 2016
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

A device comprising: a sensor; and a first circuit configured to detect when an input stimulus to the sensor satisfies one or more detection criteria, and further configured to produce a signal upon detection that causes adjustment of performance of the device; and a second circuit for processing input following detection, wherein the second circuit is configured to increase its power level following detection, relative to a power level of the second circuit prior to detection.

First claim

The invention claimed is:

1. A device comprising:
a piezoelectric micro electro-mechanical systems (MEMS) transducer having an output;
a controllable switch having a control input and configured to provide power to one of a first output or a second output;
a detection circuit banded over a frequency range and having a signal input coupled to the output of the piezoelectric MEMS transducer, wherein the detection circuit is further coupled to the first output of the controllable switch, wherein the detection circuit is configured to produce a first signal at an output of the detection circuit based on an acoustic level of the piezoelectric MEMS transducer exceeding a threshold level; and
a second circuit coupled to the second output of the controllable switch and the piezoelectric MEMS transducer,
wherein the controllable switch is configured to alternate between providing power to the detection circuit via the first output of the controllable switch and providing power to the second circuit via the second output of the controllable switch based on the first signal.

2. The device of claim 1 , wherein the detection circuit is configured to detect when the acoustic level of the piezoelectric MEMS transducer exceeds the threshold level.

3. The device of claim 2 , wherein, to detect when the acoustic level of the piezoelectric MEMS transducer exceeds the threshold level, the detection circuit is configured to detect when the acoustic level of the piezoelectric MEMS transducer exceeds the threshold level a certain number of times.

4. The device of claim 2 , wherein, to detect when the acoustic level of the piezoelectric MEMS transducer exceeds the threshold level, the detection circuit is configured to detect when an average banded acoustic level for the piezoelectric MEMS transducer for a period of time exceeds the threshold level.

5. The device of claim 1 , wherein the threshold level comprises a threshold acoustic level.

6. The device of claim 1 , wherein the piezoelectric MEMS transducer has a flat response in a voice frequency range in which the piezoelectric MEMS transducer is substantially equally sensitive to frequencies in the voice frequency range.

7. The device of claim 1 , wherein the second circuit is configured to generate a second signal at least in part based on the first signal of the detection circuit.

8. The device of claim 7 , wherein the second circuit is further configured to transmit the second signal to a digital system to cause the digital system to power on and to perform digital signal processing (DSP).

9. The device of claim 1 , wherein the detection circuit banded over the frequency range comprises the piezoelectric MEMS transducer banded by mechanics of the piezoelectric MEMS transducer in which the piezoelectric MEMS transducer mechanically has a resonant frequency such that the piezoelectric MEMS transducer does not sense frequencies outside the frequency range.

10. The device of claim 9 , wherein the mechanics comprise mechanical or hardware capabilities.

11. The device of claim 1 , wherein the detection circuit is configured to only detect a certain acoustic range.

12. The device of claim 1 , wherein the detection circuit comprises an analog circuit.

13. The device of claim 1 , wherein the device comprises an analog device.

14. The device of claim 1 , wherein the device is configured to operate at an analog level.

15. The device of claim 1 , wherein the device comprises a packaged device.

16. A method comprising:
producing, using a detection circuit banded over a frequency range, a first signal at an output of the detection circuit based on an acoustic level of a signal from a piezoelectric micro electro-mechanical systems (MEMS) transducer exceeding a threshold level; and
alternating, using a controllable switch, between providing power to the detection circuit via a first output of the controllable switch and providing power to a second circuit via a second output of the controllable switch based on the first signal, wherein the second circuit is coupled to the second output of the controllable switch and the piezoelectric MEMS transducer.

17. The method of claim 16 , further comprising detecting, using the detection circuit, when the acoustic level of the signal from the piezoelectric MEMS transducer exceeds the threshold level.

18. The method of claim 17 , wherein detecting when the acoustic level of the signal from the piezoelectric MEMS transducer exceeds the threshold level comprises detecting when the acoustic level of the signal from the piezoelectric MEMS transducer exceeds the threshold level a certain number of times.

19. The method of claim 17 , wherein detecting when the acoustic level of the signal from the piezoelectric MEMS transducer exceeds the threshold level comprises detecting when an average banded acoustic level for the signal from the piezoelectric MEMS transducer for a period of time exceeds the threshold level.

20. The method of claim 16 , wherein the threshold level comprises a threshold acoustic level.

21. The method of claim 16 , wherein the piezoelectric MEMS transducer has a flat response in a voice frequency range in which the piezoelectric MEMS transducer is substantially equally sensitive to frequencies in the voice frequency range.

22. The method of claim 16 , further comprising generating, using the second circuit, a second signal at least in part based on the first signal of the detection circuit.

23. The method of claim 22 , further comprising transmitting, using the second circuit, the second signal to a digital system to cause the digital system to power on and to perform digital signal processing (DSP).

24. The method of claim 16 , wherein the detection circuit banded over the frequency range comprises the piezoelectric MEMS transducer banded by mechanics of the piezoelectric MEMS transducer in which the piezoelectric MEMS transducer mechanically has a resonant frequency such that the piezoelectric MEMS transducer does not sense frequencies outside the frequency range.

25. The method of claim 16 , wherein the detection circuit is configured to only detect a certain acoustic range.

26. The method of claim 16 , wherein the detection circuit comprises an analog circuit.

27. The method of claim 16 , wherein the power is provided to the detection circuit via the first output of the controllable switch when the second circuit is not processing the first signal.

Assignees

• Qualcomm Inc

Inventors

• Littrell Robert John
• Gagnon Ronald
• Grosh Karl

Classifications

• H04R3/04 Primary

  for correcting frequency response · CPC title

• H04R17/02

  Microphones · CPC title

• H04R3/00 Primary

  Circuits for transducers (arrangements for producing a reverberation or echo sound G10K15/08; amplifiers H03F) · CPC title

• H04R2201/003

  Mems transducers or their use · CPC title

• H04R17/025 Primary

  using a piezoelectric polymer · CPC title