INTEGRATED MOTION PROCESSING UNIT (MPU) WITH MEMS INERTIAL SENSING AND EMBEDDED DIGITAL ELECTRONICS

• US 20120253738A1
• Filed: 06/08/2012
• Published: 10/04/2012
• Est. Priority Date: 07/06/2007
• Status: Active Grant

• Current Assignee: Invensense Incorporated (TDK Corporation)
• Original Assignee: Invensense Incorporated (TDK Corporation)
• Inventors: NASIRI, Steven S., SACHS, David, TAHERI, Babak
• Granted Patent: US 8,997,564 B2
• Time in Patent Office: Days
• US Class Current: 702/141
• CPC Class Codes: G01C 19/5769 Manufacturing; Mounting; Housings
• CPC Class Codes: G01C 19/5776 Signal processing not specific to any of the devices covered by groups G01C19/5607 - G01C19/5719
• CPC Class Codes: G01P 1/023 for acceleration measuring devices
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 15/125 by capacitive pick-up
• CPC Class Codes: G01P 15/18 in two or more dimensions
• CPC Class Codes: G01P 2015/0845 using a plurality of spring-mass systems being arranged on one common planar substrate, the systems not being mechanically coupled and the sensitive direction of each system being different
• CPC Class Codes: G01P 2015/0865 using integrated signal processing circuitry
• CPC Class Codes: G01P 2015/088 for providing wafer-level encapsulation

Abstract

A module operable to be mounted onto a surface of a board. The module includes a linear accelerometer to provide a first measurement output corresponding to a measurement of linear acceleration in at least one axis, and a first rotation sensor operable to provide a second measurement output corresponding to a measurement of rotation about at least one axis. The accelerometer and the first rotation sensor are formed on a first substrate. The module further includes an application specific integrated circuit (ASIC) to receive both the first measurement output from the linear accelerometer and the second measurement output from the first rotation sensor. The ASIC includes an analog-to-digital converter and is implemented on a second substrate. The first substrate is vertically bonded to the second substrate.

Claims

1. A device comprising:

at least one gyroscope, wherein the at least one gyroscope is operable to provide a measurement output corresponding to measurement of rotation about three axes, wherein the three axes are orthogonal, and the at least one gyroscope is disposed in a plane; and

an application specific integrated circuit (ASIC) to receive the measurement output from the at least one gyroscope, wherein the ASIC includes at least one analog to digital converter (ADC), a computation unit and a memory, the computation unit receives and processes data from the at least one gyroscope, the ASIC being implemented on a first silicon substrate,

the at least one gyroscope is vertically stacked and is substantially parallel to the first silicon substrate;

the at least one gyroscope is electrically connected to the ASIC.

2. The device of claim 1, wherein the ASIC comprises a built-in logic for analyzing data from the at least one gyroscope.

3. The device of claim 2, wherein the built-in logic is configured to detect a rotational motion and determine an axis of the rotation.

4. The device of claim 2, wherein the built-in logic includes a system of programmable interrupts permitting a user to determine a source of interrupt.

5. The device of claim 2, wherein the built-in logic includes a power management circuit capable of turning off the at least one gyroscope.

6. The device of claim 2, wherein the built-in logic includes a power management circuit capable of operating the at least one gyroscope at low power.

7. The device of claim 2, wherein the built-in logic includes a power management circuit capable of turning off the at least one gyroscope in response to the measurement output.

8. The device of claim 2, further comprising one or more measurement devices, the one or more measurement devices includes one or more of an accelerometer, a position sensor, a barometer, a geomagnetic sensor, or a temperature sensor.

9. The device of claim 8, wherein the ASIC further comprises a multiplexer to selectively provide at least one measurement output from the at least one gyroscope or one or more second measurement outputs from the one or more measurement devices.

10. The device of claim 2, wherein a pedestrian navigation system uses the measurement output of the at least one gyroscope to determine a heading.

11. The device of claim 8, wherein the one or more second measurement output from an accelerometer and the computation unit determines step count.

12. The device of claim 2, wherein the measurement output from the at least one gyroscope and the computation unit determine gestures.

13. The device of claim 2, wherein the computational unit determines an orientation of the device.

14. The device of claim 2, wherein the built-in logic is programmable by the user to detect rotational motion exceeding a pre-determined threshold for a pre-determined time period, wherein both the pre-determined threshold and the pre-determined time period is programmable by the user.

15. The device of claim 2, wherein the built-in logic is further configured to detect when motion of the device is below a pre-determined threshold, and reset biases of the at least one gyroscope.

16. The device of claim 1, further comprising a second silicon substrate to seal the at least one gyroscope within a hermetic enclosure in between the first silicon substrate and the second silicon substrate.

17. The device of claim 1, wherein the application specific integrated circuit (ASIC) further comprises a microcontroller operable to receive the digital signal from the analog-to-digital converter and process the digital signal.

18. The device of claim 17, wherein the microcontroller is operable to process the digital signal including performing an image stabilization calculation based on the digital signal or the computation unit.

19. The device of claim 1, wherein the application specific integrated circuit (ASIC) further comprises a pulse width modulator (PWM) in communication with a microcontroller, the pulse width modulator operable to drive an actuator.

20. The device of claim 19, wherein the application specific integrated circuit (ASIC) further comprises a communication interface in communication with the microcontroller.

21. The device of claim 11, further comprising a communication interface including a serial peripheral interface (SPI) or an integrated circuit (I2C) interface.

22. A motion processing module, comprising:

at least one accelerometer, wherein the at least one accelerometer is operable to provide a first measurement output corresponding to measurements of linear acceleration along three axes, wherein the three axes are orthogonal and the at least one accelerometer is disposed in a plane;

a first application specific integrated circuit (ASIC) to receive the first measurement output from the at least one accelerometer, the first ASIC being implemented on a first silicon substrate, wherein the at least one accelerometer is vertically stacked and is substantially parallel to the first silicon substrate;

the at least one accelerometer is electrically connected to the first ASIC to form a first module;

at least one gyroscope, wherein the at least one gyroscope is operable to provide a second measurement output corresponding to measurements of rotation about at least one axis, wherein the at least one gyroscope is disposed in a plane; and

a second ASIC to receive the second measurement output from the at least one gyroscope, the second ASIC being implemented on a second silicon substrate, wherein the at least one gyroscope is vertically stacked and is substantially parallel to the second silicon substrate;

the at least one gyroscope is electrically connected to the second ASIC to form a second module, wherein the first ASIC or the second ASIC includes a computation unit and a memory, wherein the computation unit receives and processes data from the at least one gyroscope or the accelerometer; and

the first module and the second module are combined within a single package.

23. The device of claim 22, wherein the first ASIC or the second ASIC comprises a built-in logic with a system of programmable interrupts permitting a user to determine a source of an interrupt.

24. The device of claim 22, wherein the first ASIC or the second ASIC further comprises a communication interface coupled to the at least one gyroscope and to the at least one accelerometer.

25. The device of claim 24, wherein the communication interface comprises a serial peripheral interface (SPI) or an integrated circuit (I2C) interface.

26. A device operable to be mounted onto a surface of a board, comprising:

at least one gyroscope wherein the at least one gyroscope is operable to provide a first measurement output corresponding to a measurement of rotation about three axes, wherein the three axes are orthogonal and the at least one gyroscope is disposed in a plane;

at least one accelerometer wherein the at least one accelerometer is operable to provide a second measurement output corresponding to a measurement of linear acceleration along three axes, wherein the three axes are orthogonal and the at least one accelerometer is disposed in the plane; and

an application specific integrated circuit (ASIC) to receive the first measurement output from the at least one gyroscope and the second measurement output from the at least one accelerometer, wherein the ASIC includes at least one Analog-to-Digital converter (ADC), a computation unit and a memory, wherein the computation unit receives and processes data from the at least one accelerometer and the at least one gyroscope, the at least one ADC operable to convert the first measurement output, and the second measurement output, to a corresponding digital signal, the ASIC being implemented on a first silicon substrate.

27. The device of claim 26, where the plane and the first silicon substrate are vertically stacked.

28. The device of claim 26, wherein the ASIC comprises a built-in logic for analyzing data from the at least one gyroscope and the at least one accelerometer.

29. The device of claim 28, wherein the built-in logic is configured to detect a rotational motion or linear motion and determine an axis of the rotation or linear motion.

30. The device of claim 28, wherein the built-in logic includes a system of programmable interrupts permitting a user to determine a source of interrupt.

31. The device of claim 28, wherein the built-in logic includes a power management circuit capable of turning off the at least one gyroscope or the at least one accelerometer in response to corresponding measurement output.

32. The device of claim 28, wherein the built-in logic includes a power management circuit capable of operating the at least one gyroscope or the at least one accelerometer at low power in response to the first measurement output and the second measurement output.

33. The device of claim 28, wherein the built-in logic includes a power management circuit capable of turning off the at least one gyroscope in response to the first measurement output or the at least one accelerometer in response to the second measurement output.

34. The device of claim 28, wherein the built-in logic includes a power management circuit capable of turning off the at least one gyroscope in response to the second measurement output or the first measurement output.

35. The device of claim 28, wherein the built-in logic includes a power management circuit capable of turning off the at least one accelerometer in response to the second measurement output or the first measurement output.

36. The device of claim 26, wherein

the second measurement output from the at least one accelerometer provides linear acceleration information;

the first measurement output from the at least one gyroscope provides centripetal acceleration information; and

the built-in logic analyzes the first measurement output and the second measurement output to determine free fall.

37. The device of claim 26, wherein the application specific integrated circuit (ASIC) further comprises a microcontroller, wherein the microcontroller is operable to process the digital signal including performing an optical image stabilization calculation based on the digital signal or the computation unit.

38. The device of claim 28, wherein the second measurement output from the at least one accelerometer and the built-in logic determine a number of steps and a step length in a pedestrian navigation system.

39. The device of claim 28, wherein the at least one gyroscope and the at least one accelerometer are attached and electrically connected to the first silicon substrate, wherein the built-in logic includes a power management circuit capable of turning off the at least one gyroscope or the at least one accelerometer in response to corresponding measurement output.

40. The device of claim 28, wherein the first silicon substrate being electrically connected to the second silicon substrate to form a single semiconductor chip, wherein the built-in logic includes a power management circuit capable of operating the at least one gyroscope or the at least one accelerometer at low power in response to the first measurement output and the second measurement output.

41. The device of claim 28, wherein the first silicon substrate being electrically connected to the second silicon substrate to form a single semiconductor chip, wherein the built-in logic includes a power management circuit capable of turning off the at least one accelerometer in response to the first measurement output or the at least one accelerometer in response to the second measurement output.

42. The device of claim 28, wherein the first silicon substrate being electrically connected to the second silicon substrate to form a single semiconductor chip, wherein the built-in logic includes a power management circuit capable of turning off the at least one gyroscope in response to the second measurement output or the at least one accelerometer in response to the first measurement output.

43. The device of claim 28, the first silicon substrate being electrically connected to the second silicon substrate to form a single semiconductor chip, wherein the built-in logic includes a power management circuit capable of turning off the at least one gyroscope in response to the second measurement output or the at least one accelerometer in response to the first measurement output.

44. The device of claim 28, wherein the first silicon substrate being electrically connected to the second silicon substrate to form a single semiconductor chip, wherein the built-in logic includes a power management circuit capable of turning on the at least one gyroscope in response to second measurement output of the at least one accelerometer.

45. The device of claim 26, wherein the first silicon substrate being electrically connected to the second silicon substrate to form a single semiconductor chip, wherein distance is determined by subtracting gravity factor from the second measurement output and double integrating the second measurement output, where in the gravity factor is determined by the first measurement output and the second measurement output.

46. The device of claim 26, wherein the first silicon substrate being electrically connected to the second silicon substrate to form a single semiconductor chip, wherein the ASIC includes a pedestrian navigation system wherein the measurement output of the at least one gyroscope determines heading.

47. The device of claim 26, wherein the first silicon substrate being electrically connected to the second silicon substrate to form a single semiconductor chip, wherein the computation unit of the ASIC and the measurement output from the at least one gyroscope determines steps count.

48. The device of claim 26, wherein the first silicon substrate being electrically connected to the second silicon substrate to form a single semiconductor chip, the measurement output from the at least one gyroscope and the computation unit determine gestures.

49. The device of claim 26, the first silicon substrate being electrically connected to the second silicon substrate to form a single semiconductor chip, the first measurement output from the at least one gyroscope, the second measurement output from the at least one accelerometer and the computation unit determine free fall.

50. The device of claim 26, the first silicon substrate being electrically connected to the second silicon substrate to form a single semiconductor chip, wherein the second measurement output from the at least one accelerometer and the built-in logic determine a number of steps and a step length in a pedestrian navigation system.

51. The device of claim 26, wherein the first ASIC or the second ASIC further comprises a communication interface coupled to the at least one gyroscope and to the at least one accelerometer.

52. The device of claim 50, wherein the communication interface comprises a serial peripheral interface (SPI) or an integrated circuit (I2C) interface.