System Module Block Diagram; Energy Management; Battery And Charging - Nokia RM-632 Service Manual

RM-632; RM-634; RM-699
System Module

System module block diagram

Energy management

Battery and charging

BL-4D battery
The phone is powered by a 3-pole BL-4D 1200 mAh battery (Li-Ion). The three poles of the battery 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.
Figure 27 Battery pin order
The battery temperature is estimated by measuring separate battery temperature NTC via the BTEMP line of
EM ASIC (N2200). This resistor is located on the main PWB, at a place where the phone temperature is closest
to the battery temperature.
Battery connector
The battery connector is a blade connector. It has three blades;
• BSI (Battery size indicator)
Issue 3 COMPANY CONFIDENTIAL Page 5 – 7
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