Charging Circuitry - Nokia RH-44 Series Troubleshooting - Bb

RH-44
Troubleshooting — BB
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 kΩ 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 baseband supports DCT3 chargers from an electrical point of view.
Both 2- and 3-wire type chargers are supported. For 3-wire charger, the control line is
ignored. (See the following figure for details.)
Page 18
4(GND) 3(BTEMP)
Figure 13: BLC-2 battery pack pin order
Figure 14: Interconnection diagram inside the battery pack
Nokia Corporation
CCS Technical Documentation
2(BSI) 1 (+)
Confidential Issue 1 04/2003