US 11,881,730 B2
Wireless charging using time-division multiplexing
Veera Venkata Siva Nagesh Polu, Mountain View, CA (US); Liang Jia, Palo Alto, CA (US); and Srikanth Lakshmikanthan, Milpitas, CA (US)
Assigned to Google LLC, Mountain View, CA (US)
Appl. No. 16/975,350
Filed by Google LLC, Mountain View, CA (US)
PCT Filed Sep. 6, 2019, PCT No. PCT/US2019/049992
§ 371(c)(1), (2) Date Aug. 24, 2020,
PCT Pub. No. WO2021/045780, PCT Pub. Date Mar. 11, 2021.
Prior Publication US 2023/0105296 A1, Apr. 6, 2023
Int. Cl. H02J 7/00 (2006.01); H02J 50/90 (2016.01); H02J 50/12 (2016.01); H02J 50/40 (2016.01)
CPC H02J 50/90 (2016.02) [H02J 7/0013 (2013.01); H02J 50/12 (2016.02); H02J 50/40 (2016.02)] 20 Claims
OG exemplary drawing
 
1. A wireless charger comprising:
one or more wireless power transmission coils comprising a plurality of coil segments, each of the coil segments being arranged to transmit power at a different region of the wireless charger;
drive circuitry configured to apply a drive signal to the one or more wireless power transmission coils;
bypass circuit paths configured to route drive signals around the respective coil segments;
switch elements configured to enable and disable the bypass circuit paths; and
control circuitry configured to (i) detect the presence of devices to be charged at the different regions of the wireless charger, and (ii) control the switch elements such that, when devices to be charged are detected for at least two of the different regions, the wireless charger alternates between charging the devices at the least two different regions;
wherein the wireless charger is configured to (i) determine a charging timeout period for at least one of the devices and (ii) determine timing for alternating between charging the devices at the least two different regions so that, when alternating between charging the devices at the least two different regions, a time period in which the coil segment for a device is not activated is less than the charging timeout period for the device.