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LGE Internal Use Only
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
3. TECHNICAL BRIEF
- 43 -
CU405 have a protective circuit for booting from USB. When the phone is booting from USB_VBUS
without Battery, booting current is insufficient. Sometimes that can break the USB port of a computer.
For this reason, CU405 do not support booting from USB.
Figure. Schematic of USB protective circuit
2
4
5
3
1
Q500
KRX102E
USB_VBUS_IN
USB_VBUS
PS_HOLD
Summary of Contents for CU405
Page 1: ...Date May 2007 Issue 1 0 Service Manual Model CU405 Service Manual CU405 Internal Use Only ...
Page 175: ...Note ...
Page 176: ...Note ...