Fig 3 Power Up Sequence - Nokia NPM-2NX Troubleshooting Manual

CCS Technical Documentation
1 Power key pressed
• After 20ms UEM enters RESET MODE if VBAT>Vmstr+
2 2) VFLASH1, Vana, Vcore, Vio and VR3 goes high.
• VCTCXO enabled by VR3 -> RFClk 19.2 MHz running.
3 Purx released
• Purx released by UEM, UEMINT goes high for 100 ms
500ms RFCLK will change 13MHz (GSM mode),
UEM starts feeding SleepClk (32 KHz) to UPP. NOTE! Sleepclock starts
running in crystal circuitry (B200) immediately when battery voltage is
supplied.
4 Software running
• Default value for Vcore is 1.5 volts and if software is running Vcore will
rise to 1.8 volts.
• Cbus (1.00MHz/GSM and 1.08MHz/TDMA) clock starts running.
Issue 1 07/02
Figure 3: Power up sequence
ãNokia Corporation
NPM-2NX
Troubleshooting
and about
SleepX goes high and
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