Power On Trouble Shooting - LG -V909DW Service Manual

4.3 Power On Trouble shooting

BATT Get the MDM_PWR_ON signal from AP and deliverd to the KPD_PWR_N(Q500)
PM8028 Power On Start
Power up Sleep XO(32.768KHz) Oscillation(C528)
goes low to high(D500)
RF Operating.
LGE Internal Use Only
VDD_MDM_MSMC(C530), VDD_MDM_MSME(C534) Power up
Normal Boot up +1.3V_MDM_RF1(C532,553), +2.2V_MDM_RF2(C536) Power up
4. 32.768KHz Oscillation (C528)
FIG 5 Power Block
Main XO(19.2MHz) Oscillation(C522, DNI) _RESET_N
5. 19.2MHz Oscillation (C522, left point)
6. +2.2V_MDM_RF2(C536)
+1.3V_MDM_RF1(C532)
3.VDD_MDM_MSMC(C530)
VDD_MDM_MSME(C534)
1. VBATT (Battery Voltage, C516, C517, C518, C519)
2. MDM_PWR_N (High
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4. TROUBLE SHOOTING
LDOs in PMIC
Low)
Only for training and service purposes