INERTIAL DEVICE WITH PEDOMETER FUNCTION AND PORTABLE ELECTRIC APPLIANCE INCORPORATING SAID INERTIAL DEVICE

• US 20070198187A1
• Filed: 01/30/2007
• Published: 08/23/2007
• Est. Priority Date: 01/30/2006
• Status: Active Grant

• Current Assignee: STMicroelectronics SRL (STMicroelectronics NV)
• Original Assignee: STMicroelectronics SRL (STMicroelectronics NV)
• Inventors: Tronconi, Michele, Pasolini, Fabio
• Granted Patent: US 8,042,390 B2
• Time in Patent Office: Days
• US Class Current: 701/220
• CPC Class Codes: G01C 22/006 Pedometers
• CPC Class Codes: G01P 15/125 by capacitive pick-up

Abstract

An inertial device that is integratable in a portable electronic device includes: an inertial sensor for generating at least one raw acceleration signal in response to accelerations caused by movements of walking and running of a user of the pedometer; and a processing unit, associated to the inertial sensor for counting a number of steps of the user of the pedometer on the basis of the raw acceleration signal. The inertial sensor and the processing unit are both encapsulated within a single package for integrated circuits, which can be coupled to a circuit board of an electronic device and is provided with at least one connection terminal for making the number of steps available to the outside world.

Claims

1. An inertial device comprising:

an inertial sensor, for generating at least one raw acceleration signal in response to accelerations caused by movements of walking and running of a user of the inertial device; and

a processing unit, associated to said inertial sensor for counting a number of steps of the user on the basis of said raw acceleration signal;

wherein said inertial sensor and said processing unit are both encapsulated within a single package for integrated circuits, which can be coupled to a circuit board of an electronic appliance and comprises at least one connection terminal for making available said number of steps to the electronic appliance.

2. The inertial device according to claim 1, wherein said processing unit comprises a conversion chain, for extracting a usable acceleration signal from said raw acceleration signal.

3. The inertial device according to claim 2, wherein said processing unit comprises a detection circuit associated to said conversion chain for detecting steps of the user on the basis of said usable acceleration signal and updating said number of steps.

4. The inertial device according to claim 3, wherein said inertial sensor is a capacitive microelectromechanical sensor and has first, second, and third detection axes that are mutually independent for supplying first, second, and third raw acceleration signals, respectively, in response to accelerations caused by movements of walking of the user, respectively, according to said first, second, and third detection axes.

5. The inertial device according to claim 4, wherein said conversion chain comprises a reading interface connectable to said inertial sensor for converting said first, second, and third raw acceleration signal cyclically in time-division, respectively, into a first, second, and third analog acceleration signal.

6. The inertial device according to claim 5, wherein said conversion chain comprises an analog-to-digital converter for converting said first, second, and third analog acceleration signals, respectively, into first, second, and third numeric acceleration signals.

7. The inertial device according to claim 6, wherein said conversion chain comprises a selection circuit, which receives said first, second, and third numeric acceleration signals and is configured for generating said usable acceleration signal on the basis of d.c. components and of a.c. components of said first, second, and third numeric acceleration signals.

8. The inertial device according to claim 7, wherein said usable acceleration signal corresponds substantially to the a.c. component selectively of one from among said first, second, and third numeric acceleration signals, having the largest d.c. component in absolute value.

9. The inertial device according to claim 5, configured so as to make said first, second, and third numeric acceleration signals available to the outside.

10. The inertial device according to claim 3, wherein said detection circuit comprises:

a counter register, storing said number of steps;

a first comparator, configured for comparing said usable acceleration signal with a threshold value and connected to said counter register for incrementing said number of steps in response to said usable acceleration signal exceeding said threshold value; and

a selective-enabling circuit, for enabling incrementing said number of steps when said usable acceleration signal is lower than said threshold value and for disabling incrementing said number of steps for a pre-determined time interval after said usable acceleration signal has exceeded said threshold value.

11. The inertial device according to claim 10, wherein said time interval is programmable.

12. The inertial device according to claim 10, wherein said selective-enabling circuit comprises an enabling logic gate, having an output connected to said counter register, and a masking circuit for blocking said enabling logic gate for said time interval, in response to a switching of said output of said enabling logic gate.

13. The inertial device according to claim 10, wherein said detection circuit comprises a threshold-updating circuit for generating said threshold value on the basis of said usable acceleration signal.

14. The inertial device according to claim 13, wherein said threshold-updating circuit comprises an envelope detector, supplying an envelope value of said usable acceleration signal, and a threshold-calculation stage, coupled to said envelope detector for generating said threshold value on the basis of said envelope value.

15. The inertial device according to claim 3, wherein said conversion chain and said detection circuit are made up of respective dedicated electronic circuits.

16. A portable electronic appliance, comprising:

an inertial device that includes;

an inertial sensor, for generating at least one raw acceleration signal in response to accelerations caused by movements of walking and running of a user of the inertial device; and

a processing unit, associated to said inertial sensor for counting a number of steps of the user on the basis of said raw acceleration signal;

wherein said inertial sensor and said processing unit are both encapsulated within a single package for integrated circuits, which can be coupled to a circuit board of an electronic appliance and comprises at least one connection terminal for making available said number of steps to the electronic appliance.

17. The electronic appliance according to claim 16, comprising a control unit separate from said processing unit of said pedometer and coupled to said inertial device through said connection terminal for receiving said number of steps.

18. The electronic appliance according to claim 16, comprising a further inertial sensor, separate from said inertial sensor of said inertial device.

19. The electronic appliance according to claim 16, wherein said processing unit comprises:

a conversion circuit structured to extract a usable acceleration signal from said raw acceleration signal; and

a detection circuit structured to detect the steps of the user based on said usable acceleration signal and update said number of steps.

20. The electronic appliance according to claim 19, wherein said detection circuit comprises:

a counter register, storing said number of steps;

a first comparator configured for comparing said usable acceleration signal with a threshold value and connected to said counter register for incrementing said number of steps in response to said usable acceleration signal exceeding said threshold value; and

a selective-enabling circuit structured to enable incrementing said number of steps when said usable acceleration signal is lower than said threshold value and disable incrementing said number of steps for a pre-determined time interval after said usable acceleration signal has exceeded said threshold value.

21. A portable electronic appliance, comprising:

a control unit for controlling operations of the appliance; and

an inertial device coupled to the control unit, encapsulated in an integrated circuit package, and structured to output a number of steps of a user of the appliance, the inertial device including;

an inertial sensor structured to generate an acceleration signal in response to accelerations caused by movements of the user; and

a processing unit coupled to the inertial sensor and structured to count the number of steps of the user based on the raw acceleration signal.

22. The electronic appliance according to claim 21, a further inertial sensor, separate from the inertial sensor of the inertial device.

23. The electronic appliance according to claim 21, wherein the processing unit comprises:

a counter register, storing the number of steps;

a first comparator configured for comparing the acceleration signal with a threshold value and connected to the counter register for incrementing the number of steps in response to the acceleration signal exceeding the threshold value; and

a selective-enabling circuit structured to enable incrementing the number of steps when the acceleration signal is lower than the threshold value and disable incrementing the number of steps for a pre-determined time interval after the acceleration signal has exceeded the threshold value.

24. The electronic appliance according to claim 21, wherein the inertial sensor and processing unit are integrated together on a semiconductor chip.