NSW-5
System Module UT5U
PAMS Technical Documentation
Page 22
Issue 1 10/00
Nokia Mobile Phones Ltd.
IBI (Intelligent Battery Interface)
Phone can be powered up by external device (accessory or similar) by
providing a start pulse to the battery signal BTEMP; this is detected by
CCONT. After that the power–up procedure is similar to pushing power–
button.
Mixed trigger to power up
It is possible that PWR–key is pushed during charger initiated power–up
procedure or charger is connected during PWR–key initiated power up
procedure. In this kind of circumstances the power–up procedure (from
the HW point of view) continues as nothing had happened.
When the Baseband HW is working normally and SW is running, SW de-
tects that both conditions are fulfilled and then acts accordingly.
Power Down
Controlled Power Down
Power down pushing PWR–key
MAD (MCU SW) detects that PWR–key is pressed long enough. After that
the lights and LCD are turned off. MCU stops all the activities it was doing
(e.g. ends a call), sends power off command to CCONT (i.e. gives a short
watchdog time) and goes to idle–task. After the delay CCONT cuts all the
supply voltages from the phone.
Note that the phone does not go to power off (from HW point of view)
when the charger is connected and PWR–key is pushed. It is shown to
user that the phone is in power off, but in fact the phone is just acting be-
ing powered off (”acting dead”).
Power down when battery voltage is discharged too low
During normal discharge the phone indicates the user that the battery will
drain after some time. If not recharged, SW detects that battery voltage is
too low and shuts the phone off through a normal power down procedure.
Anyway, if the SW fails to power down the phone, the CCONT will make a
reset and power down the phone if the battery voltage drops below 2.6 –
2.9 V.
Power down
with fault in the transmitter
If MAD receives fault indication, from the line TXF, that the transmitter is
on although it should not be, the control SW will power down the phone.
