LG LG-V909DW - 4.3 Power On Trouble shooting

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