Fully compliant with the Universal Serial Bus Specification, version 1.1.• USB hub design is compliant with Universal Serial Bus Hub Specification, revision1.1.• Single chip integrated USB hub controller with embedded proprietary processor.• Supports four bus-powered/self-powered downstream ports.• Built-in 3.3v voltage regulator allows single +5V operating voltage, resulting inreduced overall system cost.• Runs at 12Mhz frequency.• 28-pin SSOP package, both normal size (body size 209 mil) and smaller size (bodysize 150 mil) are available.
从 datasheet 上看确实不支持 usb2.0 所以你碰到的速度是正常的