Only For Training And Service Purposes - LG KP175 Service Manual

3. TECHNICAL BRIEF
E. LDO Block
There are 8 LDOs in the AD6726.
- VCORE : supplies Digital baseband Processor core and AD6726 digital core(1.8V, 80mA)
- VMEM : supplies external memory and the interface to the external memory on the digital
baseband processor (2.8V, 150mA)
- VEXT : supplies Radio digital interface and high voltage interface (2.8V, 200mA)
- VSIM : supplies the SIM interface circuitry on the digital processor and SIM card (2.85V,1.8V,
20mA)
- VRTC : supplies the Real-Time Clock module (1.8 V, 20 µA)
- VABB : supplies the analog portions of the AD6726
- VMIC : supplies the microphone interface circuitry (2.5 V, 2 mA)
- VVCXO : supplies the voltage controlled crystal oscillator ( 2.75 V, 10 mA)
F. Battery Charging Block
1. It can be used to charge Lithium Ion batteries.
Charger initialization, trickle charging, and Li-Ion charging control are implemented in hardware.
2. Over voltage protection
It will be automatically disabled when the input voltage is lower than 2.5V or high than 6.5V
3. Charging Process
- Check charger is inserted or not
- If MP26021 detects that Charger is inserted, the CC-CV charging starts.
- Exception : When battery voltage is lower than 2.6V, the trickle charge starts firstly.
- And the battery voltage reach to 2.6V the CC charging mode starts.
- And the battery voltage reach to 4.15V the charging mode changes to CV mode.
4. Pins used for charging
- nCHG_DET : charger supply Detect
- nCHG_EN :
5. TA (Travel Adaptor)
- Input voltage: AC 100V ~ 2400V, 50~60Hz
- Output voltage: DC 6.4V
- Output current: Max 400mA
6. Battery
- Li-ion battery (Max 4.2V, Nom 3.7V)
- Standard battery: Capacity - 900mAh
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Only for training and service purposes