Battery Temperature - Nokia NSM-3 Series Technical Documentation Manual

PAMS Technical Documentation
Vcc
0.850.05 Vcc
0.550.05 Vcc
SIMC
GND

Battery Temperature

The battery temperature is measured with a NTC inside the battery pack.
The BTEMP line inside transceiver has a 100k pullup to VREF. The MCU
can calculate the battery temperature by reading the BTEMP line DC–
voltage level with a CCONT (N100) A/D–converter.
Pin Name Min
3 BTEMP 0
2.1
5
1.9
90
–5
BATTERY
Issue 4 02/2002
D X
ARD ET
Typ Max Unit
1.4 V
3 V
10 20 ms
2.8 V
100 200 ms
5 %
VBATT
BSI
BTEMP
R
NTC
T
BGND
E Nokia Corporation
S
IG
Notes
Battery temperature indication
100k pullup resistor to VREF in phone
Battery package has NTC pull down resis-
tor:
47k +/–5%@+25C , B=4050+/–3%
Phone power up by battery (input)
Power up pulse width
Battery power up by phone (output)
Power up pulse width
100k pullup resistor tolerance
TRANSCEIVER
VREF
100k
CCONT
10k
BTEMP
NSM–3/3D
System Module
O
UT
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