User Guide

PAMS
Technical Documentation
NSE–8/9
System Module
Page 2– 35
Issue 1 07/99
Baseband
Functional Description
There are four actions that initiate the power up procedure of the phone;
1. pressing the power on/off button
2. connecting a charger to the phone
3. power up initiated by a pulse on BTEMP (DCT3 IBI pulse)
4. power up initiated by RTC
Because the power up procedure is somewhat different depending on the
initializing action they are described below separately. The power up
procedures are described up to the point when the system control
switches from CCONT to MAD2PR1, i.e. when power up reset (PURX) is
released.
Charger Initiated Power Up Procedure
0. INITIAL CONDITIONS:
– all components except DC/DC converter and CCONT RTC powered off
– all resets active
– battery connected
1. CHARGER ADDED:
1.1 The PSCC starts charging the battery with initial current. When
the battery voltage reaches the switcher startup voltage level, the switcher
will start up and supply the CCONT
1
, which identifies the charger
presence (VCHAR)
1.2 CCONT waits until Vdc_out exceeds 3.0 V
2
1.3 CCONT powers on its digital logic and sets the PWM output
to100%
1.4 CCONT releases the reset of its digital logic after 50 us setup
time
2. CCONT RELEASES BB, VCXO and COBBA–ANALOG
3
REGULATORS:
2.1 CCONT releases SLEEPX/VXOEna signal
2.2 CCONT waits 62 ms
4
3. AFTER 62 ms DELAY CCONT RELEASES POWER UP RESET
(PURX) AND SETS CCONT_INT SIGNAL ACTIVE:
This may take some seconds depending upon the battery / switcher being able to supply
sufficient current, if the battery is almost empty,
If charger is connected to empty battery this may take some seconds
VCXO regulator is controlled by SLEEPX/VXOEna signal. The regulator for the COBBA
analog parts must follow the VCXO regulator to enable the AFC
62 ms setup time is used for VCXO settling