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3. TECHNICAL BRIEF
Trickle Charging
Trickle charging of the main battery, enabled through MSM control and powered from VDD, is provided
by the PM6658 IC. This mode is used to raise a severely depleted battery's voltage to a level sufficient
to begin fast charging.
Valid Setting : 0, 20, 30, 40, 50, 60, 70, 80mA
The trickle charger is an on-chip programmable current source that supplies current from VDD to pin
E1 (VBAT). Trickle charging is enabled through MSM control and should be used until the main battery
reaches its desired threshold, usually about 3.0 V for Li-ion batteries. The threshold varies with battery
type and application, so there is no predefined value implemented in the detection circuits. Software
must terminate trickle charging based on battery voltage measurements at the MSM HKADC (routed
through the PMIC analog multiplexers) and the battery type - there is not a preset termination
threshold.
The charging current path and voltage monitoring path are highlighted.
LGE Internal Use Only
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes