Charging Circuitry - Nokia RH-34 Series Technical Documentation Manual

RH-34
Troubleshooting - Baseband
tor inside the battery pack on the BSI line indicates the battery size. NTC-resistor inside
the battery measures the battery temperature on the BTEMP line.
Temperature and capacity information are needed for charge control. These resistors are
connected to BSI and BTEMP pins of battery connector. Phone has 100 kW pull-up resis-
tors for these lines so that they can be read by A/D inputs in the phone.

Charging circuitry

The UEM ASIC controls charging depending on the charger being used and the battery
size. External components are needed for EMC, reverse polarity and transient protection
of the input to the baseband module. The charger connection is through the system con-
nector interface. The RH-34 baseband is designed to support DCT3 chargers from an
electrical point of view. Both 2- and 3-wire type chargers are supported. However, as
mention above, three wire chargers are treated as two.
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4(GND) 3(BTEMP)
Figure 4: BLB-2 battery pack pin order
VBATT
BSI
BTEMP
EMC
Figure 5: Interconnection diagram inside the battery pack
©2003 Nokia Corporation
CCS Technical Documentation
2(BSI) 1 (+)
Li-Ion
Overcharge /
Overdischarge
protection
Confidential Issue 1 11/2003