Nokia NPD-1 Series Troubleshooting - Bb page 11

CCS Technical Documentation
acknowledged at the rising edge of the PURX signal in order to always give the same
watchdog response time to the MCU.
The following timing diagram represents UEM start-up sequence from reset to power-on
mode.
Reference signal
PwrOnX
Charger Detection
RTC
UEMRSTX
VFlash1
VIO
VCORE
VANA
VR3
19.2MHz Clk
PURX
32kHz XTAL
Issue 1 11/2002
t1 = 20ms
t1 t2 t3 t4 t2 = 200ms
Figure 5: Power on sequence and timing
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Troubleshooting — BB
t3 = 500us
t4 = 20ms
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