Circuit arrangement with an optimized frequency response and method for calibrating a circuit arrangement

• US 10,244,315 B2
• Filed: 09/18/2017
• Issued: 03/26/2019
• Est. Priority Date: 09/19/2016
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Straeussnigg, Dietmar, Caspani, Alessandro, Bach, Elmar
• Primary Examiner(s): Jerez Lora, William A
• Application Number:
  US15/706,825
• Publication Number:
  US 20180084343A1
• Time in Patent Office: 554 Days
• Field of Search: 381 56, 381 58, 381 91, 381 92, 381124, 381303, 381320
• CPC Class Codes: B81B 7/02 containing distinct electrical or optical devices of particular relevance for their function, e.g. microelectro-mechanical systems [MEMS] B81B7/04 takes precedence
• CPC Class Codes: G01P 21/00 Testing or calibrating of apparatus or devices covered by the preceding groups
• CPC Class Codes: H04R 1/22 for obtaining desired frequency characteristic only circuit for combining transducers having different responses H04R3/00; for hearing aids H04R25/407
• CPC Class Codes: H04R 19/04 Microphones H04R19/01 takes precedence
• CPC Class Codes: H04R 2201/003 Mems transducers or their use
• CPC Class Codes: H04R 2201/401 2D or 3D arrays of transducers
• 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 29/004 for microphones H04R29/007 takes precedence
• 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 5/027 Spatial or constructional arrangements of microphones, e.g. in dummy heads

Abstract

In various embodiments, a circuit arrangement includes a calibration filter set up to receive a signal based on a first signal and to provide a calibrated signal, the first signal being a signal which is provided by an analog/digital converter and is based on an analog signal, the analog signal being provided by at least one sensor of a sensor arrangement, a filter arrangement set up to receive a signal based on the first signal and to provide a second signal, and a controller set up to select a sensor-specific control signal dependent on the frequency response of the sensor from a plurality of control signals and to provide the calibration filter with said signal, the calibrated signal being based on the first signal and the sensor-specific control signal and corresponding or substantially corresponding to a predefined spectral mask in a predefined frequency range.

Claims

1. A circuit arrangement, comprising:

a calibration filter set up to receive a signal based on a first signal and to provide a calibrated signal;

the first signal being a signal which is provided by an analog/digital converter and is based on an analog signal, the analog signal being provided by at least one sensor of a sensor arrangement,

a filter arrangement set up to receive a signal based on the first signal and to provide a second signal; and

a controller set up to select a sensor-specific control signal dependent on the frequency response of the sensor from a plurality of control signals and to provide the calibration filter with the sensor-specific control signal, the calibrated signal being based on the first signal and the sensor-specific control signal and corresponding or substantially corresponding to a predefined spectral mask in a predefined frequency range.

2. The circuit arrangement of claim 1,

wherein the sensor arrangement comprises a plurality of sensors which each provide an analog signal, at least one signal from a sensor being changed with respect to the predefined spectral mask.

3. The circuit arrangement of claim 2,

wherein the signals from a plurality of sensors of the sensor arrangement are changed with respect to a common predefined spectral mask.

4. The circuit arrangement of claim 1,

wherein at least one sensor of the sensor arrangement comprises a diaphragm, a deflection of the diaphragm from a rest position generating the analog signal.

5. The circuit arrangement of claim 4,

wherein the diaphragm is or comprises a micro-electromechanical structure.

6. The circuit arrangement of claim 1,

wherein the calibration filter is a programmable calibration filter.

7. The circuit arrangement of claim 1,

wherein the calibration filter is a recursive calibration filter.

8. The circuit arrangement of claim 1,

wherein the calibration filter comprises at least two filter coefficients.

9. The circuit arrangement of claim 8,

wherein the calibration filter comprises at least three filter coefficients.

10. The circuit arrangement of claim 1,

wherein the circuit arrangement is in the form of a pressure sensor arrangement.

11. The circuit arrangement of claim 1,

wherein the circuit arrangement is in the form of a microphone arrangement.

12. The circuit arrangement of claim 11,

wherein the microphone arrangement comprises an arrangement of a plurality of microphones;

wherein the microphones are set up as sensors of the sensor arrangement.

13. The circuit arrangement of claim 1,

wherein the filter arrangement comprises at least one of the following filters or filter functions:

a frequency-selective filter.

14. The circuit arrangement of claim 1, further comprising:

a modulator which is connected to the analog/digital converter and is set up to provide a third signal based on the calibrated signal.

15. The circuit arrangement of claim 1, further comprising:

an interface configured to provide a fourth signal which is based on the second signal;

wherein the interface is set up to provide an environment outside the circuit arrangement with the fourth signal.

16. The circuit arrangement of claim 15,

wherein the fourth signal is a single-bit signal.

17. The circuit arrangement of claim 15,

wherein the fourth signal is a multi-bit signal.

18. The circuit arrangement of claim 1,

wherein the sensor-specific control signal is dependent on a measured or estimated property of the sensor with respect to at least one of a predefined amplitude response, a predefined phase response, or a predefined group delay.

19. The circuit arrangement of claim 18,

wherein the control unit either comprises a memory or is connected to a memory;

wherein the memory storing the plurality of control signals and the controller are set up to select one of the plurality of control signals as the sensor-specific control signal depending on the measured or estimated property of the sensor and to provide the calibration filter with the sensor-specific control signal.

20. The circuit arrangement of claim 1,

wherein the calibration filter is configured to receive the signal provided by the filter arrangement.

21. The circuit arrangement of claim 1,

wherein the filter arrangement is configured to receive the calibrated signal provided by the calibration filter.

22. The circuit arrangement of claim 1,

wherein the sensor arrangement comprises at least one sensor which is set up to provide the analog signal.

23. The circuit arrangement of claim 1, further comprising:

the analog/digital converter set up to receive the analog signal and to provide the first signal.

24. A method of calibrating a circuit arrangement,

the circuit arrangement comprising a calibration filter and at least one sensor which is set up to provide a sensor signal;

the method comprising;

detecting a property of a sensor of the at least one sensor;

determining a sensor-specific control signal from a multiplicity of control signals on the basis of the detected property and a predefined spectral mask; and

providing a calibrated signal from the calibration filter based on the sensor signal as modified by the sensor-specific control signal, the sensor-specific control signal causing recursive processing with at least two signal coefficients.

25. The method of claim 24,

wherein the circuit arrangement comprises:

the calibration filter set up to receive a first signal based on the sensor signal and to provide the calibrated signal;

the first signal being a signal which is provided by an analog/digital converter and is based on an analog signal, the analog signal being based on the sensor signal,

a filter arrangement set up to receive a signal based on the first signal and to provide a second signal; and

a controller set up to select the sensor-specific control signal dependent on the frequency response of the sensor from the multiplicity of control signals and to provide the calibration filter with the sensor-specific control signal, the calibrated signal being based on the first signal and the sensor-specific control signal and corresponding or substantially corresponding to a predefined spectral mask in a predefined frequency range.