Only For Training And Service Purposes - LG CT815 Service Manual

3.10.3 Charging control
A programmable charging block in PM7540 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. PM7540 circuits monitor voltages at VCHARGER and
ICHARGE pins to determine which supply should be used and when to switch between the two
supplies.
These pins are connected to the Source (or emitter) and Drain (or collector) contacts of the pass
transistor respectively.
100~73 (%)
Figure. CT815 Battery Bar Display(Stand By Condition)
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Only for training and service purposes

U8210 Charging Control block
47~26 (%)
72~48 (%)
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3. TECHNICAL BRIEF
PM7540
Input Power
Management
5~0 (%)
25~6 (%)
LGE Internal Use Only