3. TECHNICAL BRIEF
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3.9.3.4 Pulse charging
After constant current charging of a Li-ion battery is finished, the charging continues using either constant
voltage or pulse techniques.
There are two options for implementing pulse charging:
1. By switching the battery MOSFET on and off until the battery’s open circuit voltage stays above the VMAXSEL
setting.
2. By switching the pass device on and off. This option is the preferred method for all designs. Pulse charging,
compared to constant voltage, provides better battery voltage accuracy, reaches full charge more quickly, and
dissipates less transistor power when switching from constant current charging. Pulse charging is enabled
through software and uses the same hardware as constant-current or constant-voltage charging, but
repetitiously opens and closes the charging pass transistor (or battery transistor) to deliver current pulses to the
battery.
3.9.3.5 Autonomous charging
The PMIC includes autonomous charging, a feature that lets the power management circuits conduct battery
charging with little intervention from the handset software. The autonomous charging algorithm is
implemented in a state machine; once it begins, it executes a sequence of predetermined states until charging is
completed.
3.9.3.6 LG-E730 Charging Specification
-Charging Method : CC & CV (Constant Current & Constant Voltage)
-Maximum Charging Voltage : 4.2V
-Maximum Charging Current : 700mA
-Nominal Battery Capacity : 1500mAh
-Charging time : Max. 3h 30min
- Full charge indication current (icon stop current) : 50mA