User Guide

Nokia Customer Care System Module
Company Confidential RH-21
Issue 2 07/2004  2004 Nokia Corporation. Page 13
Battery
Phone Battery
Introduction
The battery for the 3560/3520 is the BLC-2 (Li-Ion 1000 mAh).
Interface
The battery block contains BTEMP and BSI resistors for temperature measurement and
battery identification. The BSI fixed resistor value indicates the chemistry and default
capacity of a battery. BTEMP-resistor measures the battery temperature. Temperature
and capacity information is needed for charge control. These resistors are connected to
BSI and BTEMP pins of the battery connector. Phone has pull-up resistors (R202) for
these lines so that they can be read by A/D inputs in the phone (see figure below). There
also are spark gaps in the BSI and BTEMP lines to prevent ESD.
Figure 3: Battery Connections.
Batteries have a specific red line which indicates if the battery has been subjected to
excess humidity. The batteries are delivered in a "protection" mode, which gives longer
storage time. The voltage seen in the outer terminals is zero (or floating), and the battery
is activated by connecting the charger. Battery has internal protection for overvoltage
and overcurrent.
Figure 4: BLC-2 Battery contacts.
1 (+)2(BSI)3(BTEMP)4(GND)