Nokia NPC-1 Series Troubleshooting Instructions page 7

PAMS Technical Documentation
Note: In figure below, the RF_Clk frequency appears to be lower than 19.44MHz
because of a too low oscilloscope sampling frequency (2kS/s).
1 Power key pressed
• After 20ms UEM enters RESET MODE if VBAT>Vmstr+
• VFLASH1, Vana, Vcore, Vio and VR3 goes high.
• VCTCXO enabled by VR3 -> RFClk 19.44 MHz running.
2 Purx released
• Purx released by UEM, UEMINT goes high for 100 ms, SleepX goes high and
UEM starts feeding SleepClk (32 KHz) to UPP.
Note: The sleepclock starts running in the crystal circuitry (B200) immediately when
the battery voltage is supplied.
3 Software running
Issue 1 10/01
Figure 1: Power up sequence
ãNokia Corporation
Troubleshooting Instructions
NPC-1
Page 7