USB devices can use two types of power supply methods:
Self-powered: Powered by an external power source.
Bus-powered: Powered by the USB bus’s VBUS (5V).
For bus-powered devices, they can be categorized into low-power devices and high-power devices based on their power consumption:
Low-power devices: Maximum power supply of 100mA
High-power devices: Configured for 100mA during device enumeration and 500mA during normal operation.
During device enumeration, the device indicates its power configuration (self-powered/bus-powered) and power consumption to the host in the device configuration descriptor.
Ruigu Electronic 
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