System module block diagram
Energy management
Battery and charging
BL-5B battery
The phone is powered by a 3-pole BL-5B S-pack 890 mAh battery. The three poles are named VBAT, BSI and
GND where the BSI line is used to recognize the battery capacity. This is done by means of an internal battery
pull down resistor.
RM-243
System Module and User Interface
Page 6 –6 COMPANY CONFIDENTIAL Issue 1
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