Microphone and Corresponding Digital Interface

• US 20150058001A1
• Filed: 11/05/2014
• Published: 02/26/2015
• Est. Priority Date: 05/23/2013
• Status: Active Grant

• Current Assignee: Knowles Electronics Llc (Knowles Corporation)
• Original Assignee: Knowles Electronics Llc (Knowles Corporation)
• Inventors: Dai, Weiwen, Popper, Robert A.
• Granted Patent: US 10,020,008 B2
• Time in Patent Office: Days
• US Class Current: 704/231
• CPC Class Codes: G10L 25/78 Detection of presence or absence of voice signals switching of direction of transmission by voice frequency in two-way loud-speaking telephone systems H04M9/10
• CPC Class Codes: H04R 2410/00 Microphones
• 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 3/00 Circuits for transducers , loudspeakers or microphones

Abstract

Analog signals are received from a sound transducer. The analog signals are converted into digitized data. A determination is made as to whether voice activity exists within the digitized signal. Upon the detection of voice activity, an indication of voice activity is sent to a processing device. The indication is sent across a standard interface, and the standard interface is configured to be compatible to be coupled with a plurality of devices from potentially different manufacturers.

Claims

1. A method, the method comprising:

at a microphone;

receiving analog signals from a sound transducer;

converting the analog signals into digitized data;

determining whether voice activity exists within the digitized signal;

upon the detection of voice activity, sending an indication of voice activity to a processing device, wherein the indication is sent across a standard interface, the standard interface configured to be compatible to be coupled with a plurality of devices from potentially different manufacturers.

2. The method of claim 1 wherein the microphone is operated in multiple operating modes, such that the microphone selectively operate in and moves between a first microphone sensing mode and a second microphone sensing mode based upon one of more of whether an external clock is being received from a processing device, or whether power is being supplied to the microphone;

wherein within the first microphone sensing mode, the microphone utilizes an internal clock, receives first analog signals from a sound transducer, converts the first analog signals into first digitized data, determines whether voice activity exists within the first digitized signal, upon the detection of voice activity, sends an indication of voice activity to the processing device an subsequently switches from using the internal clock and receives an external clock;

wherein within the second microphone sensing mode, the microphone receives second analog signals from a sound transducer, converts the second analog signals into second digitized data, determines whether voice activity exists within the second digitized signal, upon the detection of voice activity, sends an indication of voice activity to the processing device, and uses the external clock supplied by the processing device.

3. The method of claim 1, wherein the indication comprises a signal indicating voice activity has been detected or a digitized signal.

4. The method of claim 1, wherein the transducer comprises one of a microelectromechanical system (MEMS) device, a piezoelectric device, or a speaker.

5. The method of claim 1, wherein the receiving, converting, determining, and sending are performed at an integrated circuit.

6. The method of claim 1, wherein the integrated circuit is disposed at one of a cellular phone, a smart phone, a personal computer, a wearable electronic device, or a tablet

7. The method of claim 1, wherein the receiving, converting, determining, and sending are performed when operating in a single mode of operation.

8. The method of claim 1, wherein the single mode is a power saving mode.

9. The method of claim 1, wherein the digitized data comprises PDM data or PCM data.

10. The method of claim 1, wherein the indication comprises a clock signal.

11. The method of claim 1, wherein the indication comprises one or more DC voltage levels.

12. The method of claim 1, wherein subsequent to sending the indication, a clock signal is received at the microphone.

13. The method of claim 12, wherein the clock signal is utilized to synchronize data movement between the microphone and an external processor.

14. The method of claim 12, wherein a first frequency of the received clock is the same as a second frequency of an internal clock disposed at the microphone.

15. The method of claim 12, wherein a first frequency of the received clock is different than a second frequency of an internal clock disposed at the microphone.

16. The method of claim 12, wherein prior to receiving clock, the microphone is in a first mode of operation, and receiving the clock is effective to cause the microphone to enter a second mode of operation.

17. The method of claim 1, wherein the standard interface is compatible with any combination of the PDM protocol, the I²S protocol, or the I²C protocol.

18. An apparatus, the apparatus comprising:

an analog-to-digital conversion circuit, the analog-to-digital conversion circuit being configured to receive analog signals from a sound transducer and convert the analog signals into digitized data;

a standard interface;

a processing device, the processing device coupled to the analog-to-digital conversion circuit and the standard interface, the processing device configured to determine whether voice activity exists within the digitized signal and upon the detection of voice activity, to send an indication of voice activity to an external processing device, wherein the indication is sent across the standard interface, the standard interface configured to be compatible to be coupled with a plurality of devices from potentially different manufacturers.

19. The apparatus of claim 18, wherein the indication is a signal indicating voice activity has been detected or a digitized signal.

20. The apparatus of claim 18, wherein the transducer comprises a microelectromechanical system (MEMS) device, a piezoelectric device, or a speaker.

21. The apparatus of claim 18, wherein the apparatus comprises an integrated circuit.

22. The apparatus of claim 18, wherein the integrated circuit is disposed at a cellular phone, a smart phone, a personal computer, a wearable electronic device, or a tablet

23. The apparatus of claim 18, wherein the digitized data comprises PDM data or PCM data.

24. The apparatus of claim 18, wherein the indication comprises a clock signal.

25. The apparatus of claim 18, wherein the indication comprises one or more DC voltage levels.

26. The apparatus of claim 18, wherein subsequent to sending the indication, a clock signal is received at the standard interface.

27. The apparatus of claim 26, wherein the processing device utilizes the clock signal to synchronize data movement between the microphone and the external processing device.

28. The apparatus of claim 26, wherein prior to receiving clock, the apparatus is in a first mode of operation, and receiving the clock is effective to cause the apparatus to enter a second mode of operation.

29. The apparatus of claim 18, wherein the standard interface is compatible with any combination of the PDM protocol, the I²S protocol, or the I²C protocol.