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LGE Internal Use Only
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
3. Technical Brief
Constant Current Charging
The PM7540 IC supports constant current charging of the main battery by controlling the charger
pass transistor and the battery transistor. The constant current charging continues until the battery
reaches its target voltage, 4.2V.
Constant Voltage Charging
Constant voltage charging begins when the battery voltage reaches a target voltage, 4.2V.
The end of constant voltage charging is commonly detected 10% of the full charging
current.
• Charging Method : CC & CV (Constant Current & Constant Voltage)
• Maximum Charging Voltage : 4.2V
• Maximum Charging Current : 900mA
• Nominal Battery Capacity : 1500mAh
• Charging time : Max 2.5h (Except time trickle charging)
• Full charge indication current (icon stop current) : 120mA
• Cut-off voltage : 3.20V