Nokia 8850 Manual Do Serviço
NSM–2
System Module
System Module
PAMS Technical Documentation
Page 12
Issue 1 12/1999
Nokia Mobile Phones Ltd.
Power Distribution
In normal operation the baseband is powered from the phone‘s battery.
The battery consists of one Lithium–Ion cell. An external charger can be
used for recharging the battery and supplying power to the phone.
The battery consists of one Lithium–Ion cell. An external charger can be
used for recharging the battery and supplying power to the phone.
The baseband contains parts that control power distribution to whole
phone excluding those parts that use continuous battery supply. The bat-
tery feeds power directly to the CCONT and UI (buzzer and display and
keyboard lights).
phone excluding those parts that use continuous battery supply. The bat-
tery feeds power directly to the CCONT and UI (buzzer and display and
keyboard lights).
The power management circuit CHAPS provides protection against over-
voltages, charger failures and pirate chargers etc. that would otherwise
cause damage to the phone.
voltages, charger failures and pirate chargers etc. that would otherwise
cause damage to the phone.
CCONT
SIM
+
CHARGER CONNECTOR
CHAPS
COBBA
BATTERY
PA SUPPLY
RF SUPPLIES
VBB
BASEBAND
VBAT
VCOBBA
VSIM
VBB
CNTVR
PWM
VBAT
PWRONX
PURX
VIN
UI
BACKUP
RTC
MEMORIES
MAD
LIM
VBB
Battery charging
The electrical specifications give the idle voltages produced by the ac-
ceptable chargers at the DC connector input. The absolute maximum in-
put voltage is 30V due to the transient suppressor that is protecting the
charger input. At phone end there is no difference between a plug–in
charger or a desktop charger. The DC–jack pins and bottom connector
charging pads are connected together inside the phone.
ceptable chargers at the DC connector input. The absolute maximum in-
put voltage is 30V due to the transient suppressor that is protecting the
charger input. At phone end there is no difference between a plug–in
charger or a desktop charger. The DC–jack pins and bottom connector
charging pads are connected together inside the phone.