Sensing device with a temperature sensor

Patent metadata

Field	Value
Publication number	US-10408797-B2
Application number	US-201715424720-A
Country	US
Kind code	B2
Filing date	Feb 3, 2017
Priority date	May 10, 2016
Publication date	Sep 10, 2019
Grant date	Sep 10, 2019

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.

First claim

What is claimed is:

1. An electronic device comprising:
an array of ultrasonic transducers, wherein the ultrasonic transducers comprise Piezoelectric Micromachined Ultrasonic Transducer (PMUT) devices;
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 control module comprises a processor.

3. 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.

4. 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.

5. 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.

6. 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.

7. 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.

8. 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.

9. 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.

10. The electronic device of claim 9 , wherein the external device comprises an integrated circuit.

11. 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.

12. 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, 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.

13. The electronic device of claim 12 , wherein the ultrasonic transducers comprise Piezoelectric Micromachined Ultrasonic Transducer (PMUT) devices.

14. The electronic device of claim 12 , wherein the ultrasonic transducers comprise Capacitive Micromachined Ultrasonic Transducer (CMUT) devices.

15. The electronic device of claim 12 , wherein the control module is for dynamically adjusting a gain of the drive circuit based at least in part on the temperature.

16. The electronic device of claim 12 , wherein the control module is for dynamically adjusting a phase of the drive circuit based at least in part on the temperature.

17. The electronic device of claim 12 , wherein the control module is for dynamically adjusting a gain of the receive circuit based at least in part on the temperature.

18. The electronic device of claim 12 , wherein the control module is for dynamically adjusting a phase of the receive circuit based at least in part on the temperature.

19. The electronic device of claim 12 , wherein the control module is for detecting a finger interacting with the array of ultrasonic transducers based at least in part on the temperature.

20. The electronic device of claim 12 , wherein the temperature sensor is disposed within the CMOS control layer.

21. 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, 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.

22. The method of claim 21 , 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.

23. The method of claim 21 , 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.

24. The method of claim 21 , 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.

25. The method of claim 21 , 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.

26. The method of claim 21 , 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.

27. An electronic device comprising:
an array of ultra

Assignees

• Invensense Inc

Inventors

• Apte Nikhil
• Berger Renata Melamud
• Daneman Michael
• Salvia James Christian

Classifications

• G01S7/5205

  Means for monitoring or calibrating · CPC title

• B06B2201/50

  Application to a particular transducer type · CPC title

• B06B2201/40

  with testing, calibrating, safety devices, built-in protection, construction details · CPC title

• B06B2201/20

  Application to multi-element transducer · CPC title

• B06B1/0622

  on one surface · CPC title