Battery Identification; Figure 10: Battery Identification - Nokia NSB-5 Series Technical Documentation Manual

NSB-5
System Module
The performance travel charger (3– wire charger) is controlled with PWM at a frequency
of 32Hz. When the PWM rate is 32Hz CHAPS keeps the power switch continuously in the
ON state.
SWITCH
ON
PWM (1Hz)
SWITCH
PWM (32Hz)

Battery Identification

Different battery types are identified by a pulldown resistor inside the battery pack. The
BSI line inside transceiver has a 100k pullup to VBB.
The MCU can identify the battery by reading the BSI line DC–voltage level with a CCONT
(N100) A/D–converter.
BATTERY
R
s
The battery identification line is used also for battery removal detection. The BSI line is
connected to a SIMCardDetX line of MAD2 (D300). SIMCardDetX is a threshold detector
with a nominal input switching level 0.85xVcc for a rising edge and 0.55xVcc for a falling
edge. The battery removal detection is used as a trigger to power down the SIM card
before the power is lost. The BSI contact in the battery pack is made 0.7mm shorter than
the supply voltage contacts so that there is a delay between battery removal detection
Page 28
OFF ON OFF
ON
BVOLT
Vibra Schematic
Vbb
BTEMP
100k
10k
BSI
BGND
10n

Figure 10: Battery Identification

Nokia Mobile Phones Ltd.
PAMS Technical Documentation
ON
TRANSCEIVER
BSI CCONT
MAD
SIMCardDetX
Issue 1 03/01