Nokia 8850 Manual Do Serviço
NSM–2
Disassembly & Troubleshooting Instructions
PAMS Technical Documentation
Page 9
Issue 1 12/1999
Nokia Mobile Phones Ltd.
Note
Signal
Reference
N310 PIN 8
LCDLED_ADJ
LCD BACKLIGHT BRIGHNESS ADJUST-
MENT
R310 –> UI–SWITCH (N310)
MENT
R310 –> UI–SWITCH (N310)
N310 PIN 9
LCD LIGHT
LCD LED LIGHT CURRENT
UI–SWITCH (N310) –> DISPLAY BACK-
LIGHT LEDS
UI–SWITCH (N310) –> DISPLAY BACK-
LIGHT LEDS
N400 PIN 4
IRONX
IRDA (N400) SHUTDOWN
MAD (D200) –> IRDA (N400)
MAD (D200) –> IRDA (N400)
N401 PIN 4
IRDA POWER
2.8V
N401 –> IRDA (N400)
N401 –> IRDA (N400)
R118
PWRONX
POWER ON BUTTON
POWER BUTTON (S330) –> CCONT (N100)
POWER BUTTON (S330) –> CCONT (N100)
R206
SENA
HAGAR (N505) CHIP SELECT
MAD (D200) –> HAGAR (N505)
MAD (D200) –> HAGAR (N505)
R211
VPP
FLASH PROGRAMMING VOLTAGE
N220 –> COMPOMEMORY (D210)
N220 –> COMPOMEMORY (D210)
R277
EAD
ACCESSORY DETECTION
XMICP –> CCONT (N100)
XMICP –> CCONT (N100)
*Only in NSM–2..
Testing
The MCU software enters a local mode at start–up if suitable resistors are
connected to the BTEMP and BSI lines.
NOTE! Baseband doesn’t wake up automatically when the battery voltage
is connected. Power must be switched on by
connected to the BTEMP and BSI lines.
NOTE! Baseband doesn’t wake up automatically when the battery voltage
is connected. Power must be switched on by
pressing the Power key or
inserting a waking pulse BTEMP line or
connecting a charger
In the local mode the baseband can be controlled through MBUS or
FBUS connections by a PC–locals software. Baseband internal connec-
tions are tested with selftests if possible.
FBUS connections by a PC–locals software. Baseband internal connec-
tions are tested with selftests if possible.
Parameters cannot be set accurate enough by design because of compo-
nent tolerances. Due to use of 5% resistor values, the channels of the
CCONT A/D converters need to be aligned in the production phase. With-
in battery voltage tuning the MCU software reads the A/D reading from
CCONT at 4.1V and stores this reading to emulated EEPROM memory as
a reference point. Another reference point is created by assuming that
while the input voltage is zero, A/D reading is also zero. Now the slope is
known and A/D readings can be calibrated. Calibration is included in
VBATT A/D reading task.
nent tolerances. Due to use of 5% resistor values, the channels of the
CCONT A/D converters need to be aligned in the production phase. With-
in battery voltage tuning the MCU software reads the A/D reading from
CCONT at 4.1V and stores this reading to emulated EEPROM memory as
a reference point. Another reference point is created by assuming that
while the input voltage is zero, A/D reading is also zero. Now the slope is
known and A/D readings can be calibrated. Calibration is included in
VBATT A/D reading task.