Product Principle 4-13
4.11 USB HUB Board
USB main
port
USB sub-port USB sub-port
USB sub-
port
USB sub-port
Repeater
/
Controller
Fig 4-12 Principle diagram of USB HUB board
The main functions of USB HUB board:
Compatible with the USB 2.0 standard;
One USB port can be subdivided for four USB ports (there are two ports in current products.)
Detect the plug and unplug of USB device via main port.
Charge the device connecting to USB via main port.
4.12 Trolley Power Supply
Trolley power supply provides the power to main unit system. AC-DC power supply provides the
power to main unit system when there is AC input. If there is no AC input, trolley power supply
provides the power to main unit system. Trolley power supply includes connecting board of trolley
power supply, AC-DC power supply, management board of trolley battery and two pieces of
chargeable lithium-ion batteries. The connection of each part is shown below: