LG CU920 - USB Troubleshooting

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4.12 USB Troubleshooting
USB Initial sequence is :
USB connected to CU920 power on → USB_VBUS(U700) go to 5V → USB_D+ go to 3.3V →
USB_VP and USB_VN is triggered → USB work.
USB Troubleshooting Flow
Start
U700 2pin is 5V?
USB_D+ is 3.3V?
Change the Ma in board
Check U70 0 2Pin
Check U70 0
NO
YES
YES
NO
Cable is inserted?
YES
Insert cable
NO
Pow er is on?
YES
Go to po wer on trouble shooting
NO