Patent ID: 11747885

Abstract:
Disclosed are techniques for saving power in a Universal Serial Bus (USB) repeater/re-timer between a USB host and a peripheral device by intercepting packets received from the host to predict the direction of data traffic to selectively turn off/on circuitry of a peripheral port used to receive packets from the peripheral device. If a host port determines that the host is sending a start-of-frame (SOF) packet, the direction of data flow is from the host to the peripheral device, and the repeater may turn off the peripheral port such as squelch circuitry. If the host port determines that the host is sending a non-SOF packet, such as an address token that precedes a host-to-peripheral-device data transfer or a peripheral-device-to-host data transfer, the direction of data flow is anticipated to be from the peripheral device to the host, and the repeater may re-enable the deactivated circuitry of the peripheral port.