User Guide

7 Protection

Battery and charging

Battery

Note: For technical data, see Battery endurance (Page 8–19).

This device uses a BL-5X battery. The battery pack is special designed and differs from most Nokia phones. The

BSI terminal is removed due to size limitation and the GND and VBAT is interchanged.

The BSI resistor is placed on the PWB, as only one battery capacity is supported.

Figure 123 BL-5X battery

Battery connector

The battery connector has two pogo pins for VBAT (pin B) and GND (pin A). The VBAT pin has an additional switch

between pin 2 and 3. Pin 3 is connected to the SIMCarDet pin on the UEMEK for SIM card power down. The battery

has no BSI (Battery size indicator) terminal, instead there is a BSI resistor is placed on the PWB.

When the battery is inserted, the pogo pins are pressed down to open the switch. SIM power down happens

when the battery is removed which causes the switch to close.

Figure 124 Battery connector with pogo pins

Charging

The charger interface conforms to the global Nokia charger interface. Charging is performed through the charger

input in the system connector. (See System connector (Page 8–12))

The charging is controlled by the UEMEK, and external components are needed to protect the baseband module

against EMC, reverse polarity and transient frequency deviation.

Interfaces

FM radio

The FM radio is an integrated circuit, controlled by MCU software through a serial bus interface. The wires of

the headset are used as poles of the antenna, and no other antenna is needed for FM radio reception.

RM-13/33

Nokia Customer Care System Module Description

Page 8–10 Company Confidential 9240218 (Issue 1)