Usb Trouble - LG KF690 Service Manual

4. TROUBLE SHOOTING

4.2 USB trouble

USB Initial sequence of KF690 is :
USB connected to KF690
USB_DATA is triggered
C434(USB_D+) C434(USB_D+) C434(USB_D+)
VA404(USB_VBUS) VA404(USB_VBUS) VA404(USB_VBUS)
LGE Internal Use Only
→
USB_VBUS(VA404) go to 5V
→
USB work
- 62 -
→
USB_D+(C434) go to 3.3V
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