Only For Training And Service Purposes - LG KP330 Service Manual

3. TECHNICAL BRIEF
3.9.3. Charging control
A programmable charging block in PM6658 is used for battery charging. It is possible to set limits
for the charging current. The external supply typically connects directly to pin (VCHG). The voltage
on this pin (VCHG) is monitored by detection circuitry to ascertain whether a valid external supply is
applied or not. For additional accuracy or to capture variations over time, this voltage is routed
internally to the housekeeping ADC via the analog multiplexer. PM6658 circuits monitor voltages at
VCHARGER and ICHARGE pins to determine which supply should be used and when to switch
between the two supplies.
1) Pass active transistor is "on" –
Continuously closed-loop controlled
to regulate the total current
2) Battery transistor is turned on,
connecting battery to VDD node
3) Charging current(blue) flows from
the external supply
4) Total current is set by the current
regulation loop
5) Battery voltage is routed to MSM :
MSM HKADC measures VBAT
6) Constant current charging is
finished when the battery reaches
its target voltage
4.2± 0.05V
LGE Internal Use Only
KP330 Charging Control block
3.721 ± 0.05V
KP330 Battery Bar Display(Stand By Condition)
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KP330 Operational Description
3.47± 0.05V
3.651 ± 0.05V
Copyright © 2008 LG Electronics. Inc. All right reserved.

Only for training and service purposes