Circuits and methods for wearable device charging and wired control

• US 10,218,114 B2
• Filed: 10/12/2017
• Issued: 02/26/2019
• Est. Priority Date: 10/12/2016
• Status: Active Grant

• Current Assignee: Snap, Inc.
• Original Assignee: Snap, Inc.
• Inventors: Tham, Yu Jiang, Larson, Nicholas, Brook, Peter, Patton, Russell Douglas, Alhaideri, Miran, Hong, Zhihao
• Primary Examiner(s): Tso, Edward
• Assistant Examiner(s): Omar, Ahmed
• Application Number:
  US15/782,575
• Publication Number:
  US 20180102606A1
• Time in Patent Office: 502 Days
• Field of Search: 320114
• CPC Class Codes: G02C 1/00 Assemblies of lenses with bridges or browbars
• CPC Class Codes: G02C 11/00 Non-optical adjuncts; Attachment thereof G02C7/16 takes precedence
• CPC Class Codes: G02C 11/10 Electronic devices other than hearing aids
• CPC Class Codes: G02C 5/146 having special front end
• CPC Class Codes: H01L 27/0266 using field effect transistors as protective elements
• CPC Class Codes: H01R 13/6205 Two-part coupling devices held in engagement by a magnet
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/0034 using reverse polarity correcting or protecting circuits mechanical means of polarity protection H02J7/0045
• CPC Class Codes: H02J 7/0045 concerning the insertion or the connection of the batteries
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence
• CPC Class Codes: H02J 7/04 Regulation of charging current or voltage
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: H03K 19/018557 Coupling arrangements; Impedance matching circuits
• CPC Class Codes: H04B 2203/5454 Adapter and plugs
• CPC Class Codes: H04B 2203/547 via DC power distribution
• CPC Class Codes: H04B 3/548 the power on the line being DC arrangements for feeding power H04L12/10; extracting feeding power from signals H04L25/02
• CPC Class Codes: H04B 3/56 Circuits for coupling, blocking, or by-passing of signals

Abstract

Methods and devices for wired charging and communication with a wearable device are described. In one embodiment, a symmetrical contact interface comprises a first contact pad and a second contact pad, and particular wired circuitry is coupled to the first and second contact pads to enable charging as well as receive and transmit communications via the contact pads as part of various device states.

Claims

1. A wearable device comprising:

a charge interface comprising a first charge pad and a second charge pad; and

circuitry coupled to the first charge pad and the second charge pad and configured to;

perform a charging process in a charge state where the wearable device receives an electrical charge from a first device to charge a battery during an initial charging period via the first charge pad and the second charge pad;

sense, following the initial charging period, for a charge disconnect interrupt detected via the first charge pad and the second charge pad;

in response to the charge disconnect interrupt, communicate a transition signal via the first charge pad and the second charge pad to the first device;

following the transition signal, enter a transmission state and transmit data via the charge interface from the wearable device during a first time period;

enter a receive state and receive data via the charge interface from the first device during a second time period, wherein the second time period is different from the first time period and wherein the second time period occurs after communication of the transition signal; and

return to the charge state for a second charging period following the first time period and the second time period.

2. The wearable device of claim 1 wherein the charge interface comprises a symmetrical interface configured to accept a coupling with a matching head of a charge cable in a plurality of attachment positions.

3. The wearable device of claim 2 wherein the circuitry is further configured to:

detect the coupling of the charge interface with the matching head of the charge cable;

wherein the charging process during the initial charging period is performed in response to detection of the coupling.

4. The wearable device of claim 3 wherein the charge interface further comprises a plurality of magnets configured to maintain the coupling of the charge interface with the matching head of the charge cable by maintaining a force greater than an opposing force generated by springs of a set of pogo pins of the matching head configured to connect with the first charge pad and the second charge pad.

5. The wearable device of claim 3 wherein the initial charging period is associated with a first fixed time starting upon the detection of the coupling and ending with the charge disconnect interrupt.

6. The wearable device of claim 5 wherein the second charging period is associated with a second fixed time ending with a second charge disconnect interrupt.

7. The wearable device of claim 5 wherein the second charging period is associated with a variable time period that ends with a second charge disconnect interrupt.

8. The wearable device of claim 1 wherein the circuitry is further configured to:

synchronize the wearable device with the first device using the transition signal, such that the first time period and the second time period are synchronized based on the transition signal.

9. The wearable device of claim 1 wherein the circuitry is further configured to manage discharge of a capacitor coupled between the first charge pad and the second charge pad prior to the wearable device entering the transmission state and after communication of the transition signal.

10. The wearable device of claim 1 wherein the wearable device comprises a glasses front piece, the glasses front piece comprising a temple, and the temple comprising a hinge and the charge interface, wherein an arm coupled to the hinge is configured to cover the charge interface when the arm is in an open position and to uncover the charge interface when the arm is in a closed position.

11. A system for wired charging and debugging communications between a wearable device and a debug computing device, the system comprising:

a cable comprising a head having a first connecting pin and a second connecting pin; and

the debug computing device coupled to the cable at an end away from the head, the debug computing device comprising circuitry configured to;

provide an electrical charge to charge a battery of the wearable device via the first connecting pin and the second connecting pin during an initial charging period associated with a charge state when the cable is connected to the wearable device;

transition to a charge to communicate state from the charge state following the initial charging period;

sense for a first signal from the wearable device via the cable during the charge to communicate state;

in response to detection of the first signal, cycle through a plurality of communication states before transitioning back to the charge state, wherein each state of the plurality of communication states comprises configurations for communicating data via the first connecting pin and the second connecting pin; and

return to the charge state following cycling through the plurality of communication states.

12. The system of claim 11 wherein the transition to the charge to communicate state is associated with a charger disconnect interrupt generated by the debug computing device.

13. The system of claim 11 wherein the first signal comprises a pull down signal received via the first connecting pin and the second connecting pin from the wearable device.

14. The system of claim 11 wherein the circuitry of the debug computing device is further configured to:

provide a second electrical charge to charge the battery of the wearable device via the first connecting pin and the second connecting pin during a second charging period following the return to the charge state;

transition to a second charge to communicate state from the charge state following the second charging period;

sense for a transition signal from the wearable device via the cable during the second charge to communicate state; and

in response to a failure to detect the transition signal during a fixed time associated with the second charge to communicate state, return to the charge state without transitioning to a communication state of the plurality of communication states.

15. A method for charging and communications in a wearable device, the method comprising:

detecting an electrical connection at a symmetrical contact interface of the wearable device, the symmetrical contact interface comprising a first contact pad and a second contact pad;

initiating a charge state for the wearable device in response to detection of the electrical connection at the symmetrical contact interface;

receiving an electrical charge to charge a battery of the wearable device via the symmetrical contact interface during a first period associated with the charge state;

transitioning to a charge to communicate state from the charge state following the first period;

generating a first signal associated with data communications for the wearable device during the charge to communicate state;

cycling through a plurality of communication states and ending in the charge state following generation of the first signal; and

returning to the charge state for a second period without cycling through the plurality of communication states if the first signal is not present.

16. The method of claim 15 wherein transitioning to the charge to communicate state is associated with a charger disconnect interrupt generated by the debug computing device.

17. The method of claim 15 wherein the first signal comprises a pull down signal received via the first connecting pin and the second connecting pin from the wearable device.

18. The method of claim 15 further comprising:

detecting the coupling of the symmetrical contact interface with a matching head of a charge cable;

wherein the electrical charge is received in response to detection of the coupling.

19. The method of claim 15 wherein the initial charging period is associated with a first fixed time starting upon the detection of the coupling and ending with the charge disconnect interrupt;

and

wherein the second charging period is associated with a variable time period that ends with a second charge disconnect interrupt.

20. The method of claim 15 further comprising:

discharging a capacitor coupled between the first charge pad and the second charge pad prior to the wearable device entering the transmission state and after communication of the transition signal;

wherein the wearable device comprises a glasses front piece, the glasses front piece comprising a temple, and the temple comprising a hinge and the charge interface, wherein an arm coupled to the hinge is configured to cover the charge interface when the arm is in an open position and to uncover the charge interface when the arm is in a closed position.