LG F7100 Service Manual page 26

VSIM
VCORE
VRTC
VAN
VTCXO
VMEN
Power on sequence
If a battery is inserted, the battery powers the 6 LDOs.
Then if PWRONKEY is detected, the LDOs output turn on.
REFOUT is also enabled, Reset signal is generated and send to the AD6525.
LDO block
There are 6 LDOs in the ADP3522.
Charging Process
1. Check charger is inserted or not.
2. If ADP3522 detects that Charger is inserted, the CC-CV charging starts.
3. Exception: When battery voltage is lower than 3.2V, the trickle charge (low current charge mode)
starts firstly. After the battery voltage reaches to 3.2V, the CC-CV charging starts.
Battery charging block
It can be used to charge Lithium Ion and/or Nickel Metal Hydride batteries. The phones use Li-Ion
battery only. Charger initialization, trickle charging, and constant current charging are implemented in
hardware.
Pins used for charging
CHGDET : Interrupt to AD6525 when charger is plugged.
CHG_EN : Control signal from AD6525 to charge battery.
EOC : Interrupt to AD6525 when battery is fully charged.
GATE_EN : Control signal from AD6525 to charge NiMH battery. But, not used.
TA (Travel Adaptor)
Input voltage : AC 110V ~ 240V, 50~60Hz
Output voltage : DC 5.2V( ± 0.2 V)
Output current : Max 800mA
Battery
Li-ion battery : Max 4.2V, Nom 3.7V
Standard battery : Capacity - 820mAh, Li-ion
Table 3-7 LDOs of ADP3522.
Description
2.85V (is provided to Sim card)
1.8V (is provided to the AD6525 & AD6521's digital core)
2.0V (is provided to the RTC and Backup Battary)
2.55V (is provided to the AD6521 I/O and used as microphone bias)
2.75V (is provided to VCTCXO)
2.8V (is provided to Flash)
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3. TECHNICAL BRIEF