LG G5300 Service Manual page 42

Power up sequence logic
The ADP3408 controls power on sequence.
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 is generated and send to the AD6522.
LDO block
There are 6 LDOs in the ADP3408.
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 Li-Ion charging control are implemented in
hardware.
Charging Process
1. Check charger is inserted or not.
2. If ADP3408 detects that Charger is inserted, the CC-CV charging starts.
3. Exception: When battery voltage is lower than 3.2V, the precharge (low current charge mode)
starts firstly.
4. And the battery voltage reach to 3.2V the CC-CV charging starts.
Pins used for charging
CHGDET : Interrupt to AD6522 when charger is plugged.
CHGEN : Control signal from AD6522 to charge Li+ battery.
EOC : Interrupt to AD6522 when battery is fully charged.
GATEIN : Control signal from AD6522 to charge NiMH battery. But, not used.
MVBAT : Battery voltage divider. Divide ratio is 1:2.3 and it is sensed in AD6521 AUX_ADC4.
TA (Travel Adaptor)
Input voltage : AC 85V ~ 260V, 50~60Hz
Output voltage : DC 5.2V(±0.2 V)
Output current : Max 850mA(±50mA )
Battery
Li-ion battery
Standard battery
: Max 4.2V, Nom 4.0V
: Capacity - 850mAh, Li-ion
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3. TECHNICAL BRIEF