Nokia 8390 Service Manual

NSB-8

System Module & UI

PAMS Technical Documentation

Page 20

 

ãNokia Corporation

Issue 1 01/02

nection etc. 

In sleep mode VCTCXO is shut down and 32 kHz sleep clock oscillator is used as reference
clock for the baseband.

The battery voltage, temperature, size and current are measured by the UEM controlled 
by the charging software running in the UPP. 

The charging control circuitry (CHACON) inside the UEM controls the charging current 
delivered from the charger to the battery. The battery voltage rise is limited by turning 
the UEM switch off when the battery voltage has reached 4.2 V. Charging current is 
monitored by measuring the voltage drop across a 220 mOhm resistor.    

Supply voltage regulation is controlled by UEM asic. There are five regulators used by
baseband block. 

Li-ion battery pack BLB-2 is used in NSB-8.
Nominal discharge cut-off voltage

3.1 V

Nominal battery voltage

3.6 V

Nominal charging voltage

4.2 V

VANA

2.70V

2.78V

2.86V

I

max

 = 80mA

VFLASH1

2.70V

2.78V

2.86V

I

max

 = 70mA

I

Sleep

 = 1.5mA

VSIM

1.745V

2.91V

1.8V

3.0V

1.855V

3.09V

I

max

 = 25mA

I

Sleep

 = 0.5mA

VIO

1.72V

1.8V

1.88V

I

max

 = 150mA

I

Sleep

 = 0.5mA

VCORE

1.0V

1.235V

1.425V

1.710V

1.053V

1.3V

1.5V

1.8V

1.106V

1.365V

1.575V

1.890V

I

max

 = 200mA

I

Sleep

 = 0.2mA

Default value = 1.5V in 
start-up