Power Up; Power Up When Power-Button Is Pushed - Nokia NSW-5 Series Service Manual

PAMS Technical Documentation

Power up

When the battery is connected to phone, the 32.768 kHz crystal oscillator
of the CCONT is not started until the power–button is pressed. The regu-
lators are not started. After the crystal has started, the phone is ready to
be powered up by any of the following ways.
Power up when power–button is pushed
PWRONX
VR1, VBB, VR6,
V2V
RFCEN
RFCSETTLED
RFC (VCXO)
COBBACLK
PURX
SLCLK
t1
After the PWR–key has been pushed, the CCONT gives PURX reset to
MAD and the COBBA, and turns on VR1, VBB, V2V and VR6 regulators
(if the battery voltage has exceeded 3.0 V). VR1 supplies VCXO, VBB
supplies MAD and digital parts of COBBA, and VR6 supplies analog parts
of COBBA. After the initial delay t2 the VCXO starts to give proper RFC
to COBBA that further divides it to the COBBACLK for MAD. COBBA will
output the COBBACLK only after the PURX reset has been removed. Af-
ter delay t3 the CCONT releases PURX and MAD can take control of the
operation of the phone.
After that MCU–SW in MAD detects that the PWR–key is still pushed and
shows the user that the phone is powering up by starting the LCD and
Issue 1 10/00
t2
t3
t1 < 1 ms
t2 1 – 6 ms, VCXO settled
t3 62 ms, PURX delay generated by CCONT
E Nokia Mobile Phones Ltd.
NSW-5
System Module UT5U
Page 19