Partial Off Power State for USB Charging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current computer systems lack a power state that allows for device charging through a serial bus port, such as USB, without maintaining the entire system state, which is essential for efficient power management and extended battery life.
Innovation Solution
A partial off state is introduced, where at least some part of the USB controller hardware remains powered, enabling device charging while the system state is not saved, and the system can reboot upon power switch activation, with the ability to exit this state based on trigger events or configuration settings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the system enters a shutdown state (S5) to save power, then power consumption is minimized, but the system cannot charge devices through USB ports and requires a full boot cycle to resume
Solution Approach 1:
The system is segmented into two independent power domains: a main system domain that can be fully shut down for maximum power savings, and a USB controller domain that can remain independently powered to provide device charging capability. This segmentation allows the USB subsystem to maintain functionality while the main system enters shutdown state, resolving the contradiction between power savings and charging capability.
Solution Approach 2:
A separate USB controller acts as an intermediary component that bridges the shutdown system and external devices. This intermediary maintains a minimal operational state that enables charging functionality without requiring the main system to be fully operational, thus providing adaptability while maintaining low power consumption.
2Adaptability or versatility
If the system maintains USB controller hardware powered to enable device charging, then device charging capability is preserved, but power consumption increases compared to full shutdown state
Solution Approach 1:
Instead of maintaining the entire USB subsystem fully operational, the system applies partial action by powering only the essential charging circuitry within the USB controller. This minimal operational state provides sufficient charging capability while consuming significantly less power than a fully active USB controller, thus balancing adaptability and energy consumption.
3Use of energy by moving object
If the system enters a low power state (S1-S3) to save power, then power consumption is reduced, but system state is maintained in volatile memory requiring state preservation
Solution Approach 1:
The invention extracts the USB controller functionality from the main system state management. By making the USB controller independently powered and operational during shutdown, the charging capability is taken out from the volatile system state, eliminating the need to preserve USB-related state in memory while enabling charging in the shutdown state.
Data Source
AI summary
The computer system responds to a first trigger event to enter a partial off state in which a boot cycle is required to return to a working state. A device plugged into a serial bus port can be charged in the partial off state. A configuration register or runtime environment controls whether the computer system enters the partial off state in response to a trigger event. The computer system stays in the partial off state until another trigger event returns the computer system to the working state. In some implementations, the computer system leaves the partial off state and enters the shutdown state after an unplug event, a predetermined amount of time after an unplug event, a predetermined amount of time after entering the partial off state, a predetermined amount of time after charging of a device is complete, or any combination of such events.