SENSING DEVICE WITH A TEMPERATURE SENSOR

• US 20170328866A1
• Filed: 02/03/2017
• Published: 11/16/2017
• Est. Priority Date: 05/10/2016
• Status: Active Grant

• Current Assignee: Invensense Incorporated (TDK Corporation)
• Original Assignee: Invensense Incorporated (TDK Corporation)
• Inventors: APTE, Nikhil, BERGER, Renata Melamud, DANEMAN, Michael, SALVIA, James Christian
• Granted Patent: US 10,408,797 B2
• Time in Patent Office: Days
• CPC Class Codes: B06B 1/0207 Driving circuits specially adapted for particular applications, see the relevant subclass, e.g. G01; circuits for steering transducer arrays G10K11/34; basic circuits H03
• CPC Class Codes: B06B 1/0292 Electrostatic transducers, e.g. electret-type
• CPC Class Codes: B06B 1/0622 on one surface
• CPC Class Codes: B06B 2201/20 Application to multi-element transducer
• CPC Class Codes: B06B 2201/40 with testing, calibrating, safety devices, built-in protection, construction details
• CPC Class Codes: B06B 2201/50 Application to a particular transducer type
• CPC Class Codes: G01N 29/04 Analysing solids using acoustic emission techniques G01N29/14
• CPC Class Codes: G01N 29/30 Arrangements for calibrating or comparing, e.g. with standard objects
• CPC Class Codes: G01N 29/326 compensating for temperature variations
• CPC Class Codes: G01N 29/38 by time filtering, e.g. using time gates
• CPC Class Codes: G01N 29/4463 Signal correction, e.g. distance amplitude correction [DAC], distance gain size [DGS], noise filtering
• CPC Class Codes: G01S 7/5205 Means for monitoring or calibrating
• CPC Class Codes: G01S 7/521 Constructional features

Abstract

An electronic device including an array of ultrasonic transducers, a temperature sensor for determining a temperature of the array of ultrasonic transducers, and a control module communicatively coupled to the array of ultrasonic devices and the temperature sensor. The control module is for receiving the temperature and for controlling operation of the array of ultrasonic transducers based at least in part on the temperature.

Claims

1. An electronic device comprising:

an array of ultrasonic transducers;

a temperature sensor for determining a temperature of the array of ultrasonic transducers; and

a control module communicatively coupled to the array of ultrasonic devices and the temperature sensor, the control module for receiving the temperature and for controlling operation of the array of ultrasonic transducers based at least in part on the temperature.

2. The electronic device of claim 1, wherein the ultrasonic transducers comprise Piezoelectric Micromachined Ultrasonic Transducer (PMUT) devices.

3. The electronic device of claim 1, wherein the ultrasonic transducers comprise Capacitive Micromachined Ultrasonic Transducer (CMUT) devices.

4. The electronic device of claim 1, wherein the control module comprises a processor.

5. The electronic device of claim 1, wherein the control module is for dynamically adjusting a receive window for receiving ultrasonic signals based at least in part on the temperature.

6. The electronic device of claim 1 further comprising a drive circuit for driving transmission of ultrasonic signals from at least one ultrasonic transducer of the array of ultrasonic transducers, wherein the control module is for dynamically adjusting a gain of the drive circuit based at least in part on the temperature.

7. The electronic device of claim 1 further comprising a drive circuit for driving transmission of ultrasonic signals from at least one ultrasonic transducer of the array of ultrasonic transducers, wherein the control module is for dynamically adjusting a phase of the drive circuit based at least in part on the temperature.

8. The electronic device of claim 1 further comprising a receive circuit for receiving reflected ultrasonic signals from at least one ultrasonic transducer of the array of ultrasonic transducers, wherein the control module is for dynamically adjusting a gain of the receive circuit based at least in part on the temperature.

9. The electronic device of claim 1 further comprising a receive circuit for receiving reflected ultrasonic signals from at least one ultrasonic transducer of the array of ultrasonic transducers, wherein the control module is for dynamically adjusting a phase of the receive circuit based at least in part on the temperature.

10. The electronic device of claim 1, wherein the control module is for detecting a finger interacting with the array of ultrasonic transducers based at least in part on the temperature.

11. The electronic device of claim 1, further comprising:

an external interface, and

an external device communicatively coupled to the control module via the external interface.

12. The electronic device of claim 11, wherein the external device comprises an integrated circuit.

13. The electronic device of claim 1, further comprising:

a CMOS control layer, wherein the array of ultrasonic transducers is coupled to the CMOS control layer, and wherein the temperature sensor is disposed within the CMOS control layer.

14. An electronic device comprising:

an array of ultrasonic transducers for generating and receiving ultrasonic signals;

a CMOS control layer coupled to the array of ultrasonic transducers, the CMOS control layer comprising;

a plurality of drive circuits for driving transmission of ultrasonic signals from ultrasonic transducers of the array of ultrasonic transducers; and

a plurality of receive circuits for receiving reflected ultrasonic signals from ultrasonic transducers of the array of ultrasonic transducers;

an acoustic coupling layer overlying the array of ultrasonic transducers, wherein the ultrasonic signals are propagated through the acoustic coupling layer;

a temperature sensor for determining a temperature of at least one of the array of ultrasonic transducers and the acoustic coupling layer; and

a control module communicatively coupled to the array of ultrasonic devices and the temperature sensor, the control module for receiving the temperature and for controlling operation of the array of ultrasonic transducers based at least in part on the temperature.

15. The electronic device of claim 14, wherein the ultrasonic transducers comprise Piezoelectric Micromachined Ultrasonic Transducer (PMUT) devices.

16. The electronic device of claim 14, wherein the ultrasonic transducers comprise Capacitive Micromachined Ultrasonic Transducer (CMUT) devices.

17. The electronic device of claim 14, wherein the control module is for dynamically adjusting a receive window for receiving ultrasonic signals based at least in part on the temperature and an acoustic impedance of the acoustic coupling layer.

18. The electronic device of claim 14, wherein the control module is for dynamically adjusting a gain of the drive circuit based at least in part on the temperature.

19. The electronic device of claim 14, wherein the control module is for dynamically adjusting a phase of the drive circuit based at least in part on the temperature.

20. The electronic device of claim 14, wherein the control module is for dynamically adjusting a gain of the receive circuit based at least in part on the temperature.

21. The electronic device of claim 14, wherein the control module is for dynamically adjusting a phase of the receive circuit based at least in part on the temperature.

22. The electronic device of claim 14, wherein the control module is for detecting a finger interacting with the array of ultrasonic transducers based at least in part on the temperature.

23. The electronic device of claim 14, wherein the temperature sensor is disposed within the CMOS control layer.

24. A method for operating a fingerprint sensor comprising an array of ultrasonic transducers and a temperature sensor, the method comprising:

determining a temperature of the fingerprint sensor at the temperature sensor; and

controlling operation of the array of ultrasonic transducers based at least in part on the temperature.

25. The method of claim 24, wherein the controlling the operation of the array of ultrasonic transducers at least in part on the temperature comprises:

dynamically adjusting a receive window for receiving ultrasonic signals based at least in part on the temperature.

26. The method of claim 24, wherein the controlling the operation of the array of ultrasonic transducers at least in part on the temperature comprises:

dynamically adjusting a gain of a drive circuit of the fingerprint sensor based at least in part on the temperature.

27. The method of claim 24, wherein the controlling the operation of the array of ultrasonic transducers at least in part on the temperature comprises:

dynamically adjusting a phase of a drive circuit of the fingerprint sensor based at least in part on the temperature.

28. The method of claim 24, wherein the controlling the operation of the array of ultrasonic transducers at least in part on the temperature comprises:

dynamically adjusting a gain of a receive circuit of the fingerprint sensor based at least in part on the temperature.

29. The method of claim 24, wherein the controlling the operation of the array of ultrasonic transducers at least in part on the temperature comprises:

dynamically adjusting a phase of a receive circuit of the fingerprint sensor based at least in part on the temperature.

30. The method of claim 24, wherein the controlling the operation of the array of ultrasonic transducers at least in part on the temperature comprises:

detecting a finger interacting with the array of ultrasonic transducers based at least in part on the temperature.