US-20260128615-A1 - POWER MANAGEMENT SYSTEM FOR AN INPUT DEVICE

US20260128615A1US 20260128615 A1US20260128615 A1US 20260128615A1US-20260128615-A1

Abstract

A computer mouse includes a power interface circuit (PIC) electrically and communicatively coupled to a processor(s), the power interface circuit operable to electrically couple to and receive power from a plurality of different types of external power sources including at least a first type of external wireless power source operable to wirelessly provide power to the computer mouse at a voltage and a first current and a second type of external wireless power source operable to wirelessly provide power to the computer mouse at the voltage and a second current. The PIC generates and sends type data to the processor(s) indicating whether the first type or the second type of external wireless power source is wirelessly and electrically coupled to the power interface circuit. The computer mouse changes its power consumption characteristics based on whether the first or second type of external wireless power source is coupled to the PIC.

Inventors

Laurent Plancherel
Thomas Marriott-Dodington

Assignees

LOGITECH EUROPE S.A.

Dates

Publication Date: 20260507
Application Date: 20251229

Claims (20)

1 . A computer mouse comprising: supporting electronics including one or more processors and peripheral subsystems; and a power management system including a multiplexor electrically coupled to a plurality of input branches comprising: a bypass branch configured to receive power from an external wireless power source and provide a regulated voltage directly to the supporting electronics; a supercapacitor branch comprising: a charge storage device; and a current limiter that includes: a floating low-dropout regulator biased to regulate a voltage across a resistive element to generate substantially constant charging current; and a second low-dropout regulator configured to cap the charge storage device voltage within an operational range; and a battery branch configured to deliver stepped-up voltage from an internal user-replaceable battery, wherein the multiplexor prioritizes the bypass branch over the supercapacitor branch over the battery branch, and wherein the multiplexor is configured to switch among branches without inducing a reset of the supporting electronics.
2 . The computer mouse of claim 1 , wherein the supercapacitor branch further comprises a third stage configured to inhibit reverse current from the charge storage device into the second low-dropout regulator when the charge storage device sources power to the supporting electronics.
3 . The computer mouse of claim 1 , wherein the power management system is configured such that a total allowed current from the external wireless power source simultaneously supplies the supporting electronics via the bypass branch and charges the charge storage device via the supercapacitor branch without exceeding 60 mA.
4 . The computer mouse of claim 1 , wherein the bypass branch comprises a step-down regulator that maintains an output voltage not greater than 3.6 V to align with the operating voltage range of the supporting electronics.
5 . The computer mouse of claim 1 , wherein the power management system includes a voltage detector having a threshold that, upon the charge storage device attaining an end-of-charge state, causes the multiplexor to source power from the supercapacitor branch and, upon the charge storage device voltage dropping below the threshold, reselects the bypass branch when the external wireless power source is available.
6 . The computer mouse of claim 1 , wherein the charge storage device comprises a supercapacitor operative between approximately 2.0 V and 3.0 V, and the supercapacitor branch optionally includes a downstream voltage step-up circuit to extend usable operation of the charge storage device down to approximately 1.0 V.
7 . The computer mouse of claim 1 , wherein the power management system is configured to maintain a minimum aggregate current draw to ensure continuous wireless power emission from the external wireless power source and dynamically allocate current between the bypass branch and the supercapacitor branch based on a movement state detected by an optical sensor of the computer mouse.
8 . The computer mouse of claim 1 , wherein the multiplexor is self-powered to draw operating power from any selected branch and is configured with a switching latency less than approximately 100 microseconds so as not to induce a reset of the supporting electronics.
9 . A method of operating a computer mouse comprising: detecting availability of an external wireless power source and selecting a bypass branch to provide regulated power directly to supporting electronics of the computer mouse; concurrently charging a charge storage device via a supercapacitor branch that includes a current limiter with a floating low-dropout regulator generating substantially constant charging current across a resistive element and a protection low-dropout regulator that caps a voltage of the charge storage device within an operational range; upon the charge storage device reaching an end-of-charge state, switching the source of power to the supercapacitor branch and, upon the charge storage device voltage dropping below a threshold, switching back to the bypass branch when the external wireless power source is available; when the external wireless power source is unavailable, selecting a battery branch to power the supporting electronics; and maintaining a minimum aggregate current draw and allocating current between the bypass branch and the supercapacitor branch responsive to a movement state of the computer mouse to ensure continuous wireless power emission from the external wireless power source.
10 . The method of claim 9 , wherein the switching and selecting is performed by a multiplexor, the method further comprising: detecting a voltage threshold associated with the charge storage device using a push-pull voltage detector; and in response to detecting the voltage threshold, driving gate states of switching transistors that implement the multiplexor to inhibit leakage from the battery branch into the supercapacitor branch during a transition to battery-sourced operation.
11 . The method of claim 9 , further comprising maintaining a constant floor current draw from the external wireless power source that is at least 30 mA to signal a continuous charge request, and dynamically increasing bypass-branch current when the computer mouse is moving to keep the supporting electronics adequately powered while charging the charge storage device.
12 . The method of claim 9 , further comprising scheduling a periodic current-check interval when the charge storage device is in an end-of-charge state to prompt the external wireless power source to resume emission and reduce wake-up latency when the computer mouse is placed on the wireless charging surface.
13 . The method of claim 9 , further comprising regulating the bypass branch with a low-dropout step-down device to maintain an output in the range of approximately 2.8 to 3.6 volts aligned to an operating voltage of the supporting electronics.
14 . The method of claim 9 , wherein maintaining the minimum aggregate current draw includes, when the computer mouse is stationary, drawing at least about 30 mA and, when the computer mouse is moving, allocating about 10-20 mA to the bypass branch while 30-40 mA charges the charge storage device to ensure continuous wireless emission from the external power source.
15 . A method of controlling power consumption characteristics of a computer mouse comprising: measuring available current from an external wireless power source and regulating bypass-branch voltage to avoid exceeding an operating voltage of supporting electronics; adapting charging rate of a charge storage device by modulating a floating low-dropout regulator bias to maintain substantially constant charging current while maintaining a predetermined maximum total input current; suppressing inclusion of movement data in periodic operational reports to a host computing device when the computer mouse is stationary on a high-current stationary charger; and restoring inclusion of movement data and reallocating current to the bypass branch when the computer mouse is in motion on a low-current charging mat.
16 . The method of claim 15 , wherein adapting the charging rate comprises: monitoring a sequence of measured current plateaus associated with incremental increases in charge storage device voltage; and reducing charging current in discrete steps as the protection low-dropout regulator approaches regulation.
17 . The method of claim 15 , further comprising operating visual output elements in a first lighting pattern when the computer mouse is charging during motion on a low-current charging mat and in a second, distinct lighting pattern when the computer mouse is charging while stationary on a higher-current charger, the lighting patterns indicating respective charging modes to a user.
18 . The method of claim 15 , further comprising receiving type data as a binary sequence operating between about 2 kHz and 10 kHz from a load switch in a removable modular insert and increasing the charging rate to at least double when a second type of external wireless power source is identified based on the type data.
19 . The method of claim 15 , further comprising detecting a voltage threshold associated with the charge storage device using a push-pull voltage detector and, in response, driving gate states of switching transistors that implement a multiplexor to inhibit leakage from a battery branch into a supercapacitor branch during a transition to battery-sourced operation.
20 . The method of claim 15 , further comprising maintaining a constant floor current draw from the external wireless power source that is at least 30 mA to signal a continuous charge request, and dynamically increasing bypass-branch current when the computer mouse is moving to keep the supporting electronics adequately powered while charging the charge storage device.

Description

CROSS-REFERENCES PARAGRAPH FOR RELATED APPLICATIONS This application is a Continuation Application of application Ser. No. 17/958,256, filed Sep. 30, 2022, entitled “POWER MANAGEMENT SYSTEM FOR AN INPUT DEVICE,” the disclosure of which is herein incorporated by reference in its entirety for all purposes. The following regular U.S. patent applications (including this one) are being filed concurrently, and the entire disclosure of the other applications are incorporated by reference into this application for all purposes: Application Ser. No. 17,958,255, filed Sep. 30, 2022, entitled “WIRELESS CHARGING FOR AN INPUT DEVICE” (U.S. Pat. No. 12,001,620); andApplication Ser. No. 17/958,256, filed Sep. 30, 2022, entitled “POWER MANAGEMENT SYSTEM FOR AN INPUT DEVICE.” BACKGROUND Wireless peripheral devices (e.g., computer mice, keyboards, speakers, ear buds, smart wearables, etc.) are widely used and can provide portability and convenience, but may be subject to poor battery life. Although battery technology continues to improve, most contemporary peripheral devices require a charging cable to periodically recharge internal rechargeable batteries, which can be cumbersome, limiting, and can require the use of a hardwired cable to be used with wireless technology, which can defeat the purpose of the wireless technology in general. Furthermore, the rechargeable battery (e.g., lithium-ion battery) and related charging infrastructure (e.g., input/output port) may add considerable manufacturing cost and weight to the device, which is generally not preferrable in higher end gaming peripheral devices. Better solutions are needed. BRIEF SUMMARY In certain embodiments, a computer mouse comprises: a housing configured to receive a removable first charge storage device; an interface configured to wirelessly receive power from an external power source; a second charge storage device; and a multiplexor (MUX) including: an output coupled to one or more processors; and a set of inputs coupled to the first charge storage device, the interface, and the second charge storage device. The MUX can be configured to electrically couple the interface to the one or more processors based on a determination that the external power source is electrically coupled to and providing power to the interface; the MUX can be configured to electrically couple the second charge storage device to the one or more processors based on a determination that the external power source is electrically coupled to the interface but is not currently providing power to the interface; and the MUX can be configured to electrically couple the first charge storage device to the one or more processors based on a determination that the first charge storage device is electrically coupled to the MUX and the external power source is not coupled to or not providing power to the interface. In some aspects, the removable first charge storage device can be a removable battery, and the first charge storage device can be determined to be electrically coupled to the MUX when the first charge storage device has a voltage supply level above a threshold value (or when detected to be simply coupled thereto). The interface can be configured to receive a removable modular insert that, when inserted into the interface, enables the computer mouse to wirelessly receive power from the external power source. The external power source can be a charging mouse pad configured to wirelessly provide power to the interface via electromagnetic induction when the computer mouse is placed on or near the charging mouse pad. The second charge storage device (e.g., a supercapacitor) can be configured to be charged by the external power source via a charging circuit. In some embodiments, the charging circuit includes a current limiter comprising: a first low-dropout voltage (LDO) regulator circuit that is biased in a floating output configuration; a second LDO regulator circuit configured to regulate its output voltage to a level that is within a normal operational range of the second charge storage device, wherein the first LDO regulates its output voltage across an output resistor thereby generating a constant current that passes through the second LDO and charges the second charge storage device until the second LDO reaches and regulates at a predetermined voltage, thereby causing the first LDO to stop regulating until the output of the second LDO drops below the predetermined voltage. In certain embodiments, a total allowed current supplied by the external power source is between 40-60 mA, wherein the external power source is configured to simultaneously provide power to the one or more processors and charge the second charge storage device without exceeding the total allowed current. In some embodiments, a method of operating a computer mouse comprises: determining whether an external wireless power source is coupled to an interface configured to transfer power from the external wireless power source t