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.
LGE Internal Use Only
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
3. TECHNICAL BRIEF
- 39 -
U8210 Charging Control block
100~73 (%)
72~48 (%)
47~26 (%)
25~6 (%)
5~0 (%)
PM7540
Input Power
Management
Figure. CT815 Battery Bar Display(Stand By Condition)
Summary of Contents for CT815
Page 1: ...Date May 2009 Issue 1 0 Service Manual Model CT815 Service Manual CT815 Internal Use Only ...
Page 221: ...Note ...
Page 222: ...Note ...