4. TROUBLE SHOOTING
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Only for training and service purposes
LGE Internal Use Only
4.9 Power ON Troubleshooting
The main power source of LGP880 is provided by MAX77663.
Power ON sequence of LGP880 is,
PWR key press -> PWR_ON_KEY go to low (VA102) -> MAX77663 Power Up -> +1V2_TPS_VRTC (C5014) -> +1V2_
TPS_VCORE (C5023) -> +1V8_TPS_AVDD_OSC(C5015) -> AP_32K_CLK_IN(R5015) ->+1V2_TPS_VDDR(C5028),
+3V3_TPS_VUSB(C5010) -> +1V8_TPS_VIO(C5027) -> GPS_32K_CLK_IN, WLAN_32K_CLK_IN (R5036)->+1V2_TPS_
VPLL(C5008),+1V0_TPS_VDDRHS(C5009) -> +2V85_TPS_VMEM(C5011) , AP_VBUS_DET(R5030) ->AP_SYS_RESET_N
(R5008) goes to high
The main power source of LGP880 is provided by MAX77663.
Power ON sequence of LGP880 is,
PWR key press
PWR_ON_KEY go to low (VA102)
MAX77663 Power Up
+1V2_TPS_VRTC (C5014)
+1V2_TPS_VCORE (C5023)
+1V8_TPS_AVDD_OSC(C5015)
AP_32K_CLK_IN(R5015)
+1V2_TPS_VDDR(C5028), +3V3_TPS_VUSB(C5010)
+1V8_TPS_VIO(C5027)
GPS_32K_CLK_IN,
WLAN_32K_CLK_IN (R5036)
+1V2_TPS_VPLL(C5008),+1V0_TPS_VDDRHS(C5009)
+2V85_TPS_VMEM(C5011) , AP_VBUS_DET(R5030)
AP_SYS_RESET_N (R5008) goes to high
START
Note : LID &
ACOK has no
debounce time.
30ms debounce filter
EN0
LD04=1.2V
(VDD_RTC)
SD1=1.2V
(VDD_CORE)
LD06=1.8V
(AVDD_OSC,
USB_PLL,
HDMI_PLL)
32K_OUT
SD3=1.2V
(VDDIO_DDR)
LDO2=3.3V
(AVDD_USB,AVDD_HDMI)
SD2=1.8V
(VDDIO_XXX)
GPIO4 (32K_OUT1)
LDO0=1.2V
(AVDD_PLLA_C)
LDO1=1.0V
(VDD_DDR_HS)
LDO5=2.8V
(VDD_DDR_RX)&
GPIO1=VBUS_DET
nRST_IO
(SYS_RESET_N)
(Td)
1.28ms
1.28ms
1.28ms
1.28ms
1.28ms
1.28ms
36 msec
Power-OFF in reverse order.