US Patent No. 9,804,977

UNIVERSAL SERIAL BUS SMART HUB


Patent No. 9,804,977
Issue Date October 31, 2017
Title Universal Serial Bus Smart Hub
Inventorship Atish Ghosh, Austin, TX (US)
Cecil G. Chenault, Leander, TX (US)
Pragash Mangalapandian, Chennai (IN)
Mark Bohm, Village of Bear Creek, TX (US)
Assignee MICROCHIP TECHNOLOGY INCORPORATED, Chandler, AZ (US)

Claim of US Patent No. 9,804,977

1. A USB hub comprising:
a hub upstream port;
a plurality of hub downstream ports;
a processor;
a memory communicatively coupled to the processor for storing USB host stack code and a plurality of configuration parameters;
a USB hub core having a core upstream port and a plurality of core downstream ports, the USB hub core operable to implement
a USB hub interface between the core upstream port and the plurality of core downstream ports; and

a plurality of multiplexors, each of the plurality of multiplexors connected to a respective one of the plurality of core
downstream ports, and each multiplexor having:

a first port communicatively coupled to one of the hub downstream ports,
a second port communicatively coupled to one of the plurality of core downstream ports,
a third port communicatively coupled to the processor, and
a select input communicatively coupled to the processor and operable to communicatively couple the first port with the second
port, the third port, or both the second port and the third port, the select input of each of the plurality of multiplexors
being independently controllable by the processor for independent control of the connections provided by each of the plurality
of multiplexors;

wherein the processor is configured:
to detect when a USB device is coupled to a first one of the plurality of hub downstream ports,
to control the select input of a first multiplexor connected to the first hub downstream port so that the first port is connected
to the third port,

to run the USB host stack code,
to enumerate the USB device,
charge the USB device using a custom electrical handshake;
charge the USB device using a custom message-based handshake;
obtain a product ID (PID) and a vendor ID (VID) from the USB device,
use the PID and the VID to determine a custom battery charging protocol for the USB device,
and cause the USB hub to charge the USB device a specific battery charging protocol corresponding to the USB device, the specific
battery charging protocol one of the custom electrical handshake and the custom message-based handshake.