Battery Charging Block - LG MG120a Service Manual

3. TECHNICAL BRIEF
E. LDO Block
There are 8 LDOs in the AD6720.We only use 7 of them.
-VCORE : supplies Digital baseband Processor core and AD6720 digital core
-VMEM : supplies external memory and the interface to the external memory on the
digital baseband processor (1,8V or 2.8V, 150mA)
-VEXT : supplies Radio digital interface and high voltage interface (2.8V, 170mA)
-VSIM : supplies the SIM interface circuitry on the digital processor and SIM card (2.85V,
20mA)
-VRTC : supplies the Real-Time Clock module (1.8 V, 20A)
-VMIC : supplies the microphone interface circuitry (2.5 V, 1 mA)
-VVCXO : supplies the voltage controlled crystal oscillator ( 2.75 V, 10 mA)

3.3.3 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.
Figure 3-5: SIM Interface of AD6720
- 24 -