LG KU950 Service Manual page 48

3.10.3.3. Charging control
A programmable charging block in PM6650-1M 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. PM6650-1M 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.
4.2V~3.82V
100~61 (%)
Figure. KU950 Battery Bar Display (Standby condition)
3.71V~3.67V
3.81V~3.72V
33~16 (%)
61~33 (%)
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3. TECHNICAL BRIEF
3.48V~3.22V
3.66V~3.49V
3~0 (%)
16~3 (%)