EFM32WG Datasheet, PDF (100/834 Pages) List of Unclassifed Manufacturers – The EFM32WG Wonder Gecko is the ideal choice for demanding 8-, 16-, and 32-bit energy sensitive applications.

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Table 9.1. RMU Reset Cause Register Interpretation
Register Value
0bXXXX XXXX XXXX XXX1
0bXXXX XXXX 0XXX XX10
0bXXXX XXXX XXX0 0100
0bXXXX XXXX XXXX 1X00
0bXXXX XXXX XXX1 XX00
0bXXXX X000 0010 0000
0bXXXX X000 01X0 0000
0bXXXX X000 1XX0 0XX0
0bXXXX X001 1XX0 0XX0
0bXXXX X010 XXX0 0000
0bXXXX X100 XXX0 0000
0bXXXX 1XXX XXXX 0XX0
0bXXX1 XXXX XXXX 0XX0
0bXX1X XXXX XXXX 0XX0
0bX1XX XXXX XXXX 0XX0
0b1XXX XXXX XXXX 0XX0
Cause
A Power-on Reset has been performed. X bits are don't care.
A Brown-out has been detected on the unregulated power.
A Brown-out has been detected on the regulated power.
An external reset has been applied.
A watchdog reset has occurred.
A lockup reset has occurred.
A system request reset has occurred.
The system as woken up from EM4.
The system as woken up from EM4 on an EM4 wakeup reset request from pin.
A Brown-out has been detected on Analog Power Domain 0 (AVDD0).
A Brown-out has been detected on Analog Power Domain 1 (AVDD1).
A Brown-out has been detected by the Backup BOD on VDD_DREG.
A Brown-out has been detected by the Backup BOD on BU_VIN.
A Brown-out has been detected by the Backup BOD on unregulated power
A Brown-out has been detected by the Backup BOD on regulated power.
The system has been in Backup mode.
Note
When exiting EM4 with external reset, both the BODREGRST and BODUNREGRST in
RSTCAUSE might be set (i.e. are invalid)
9.3.2 Power-On Reset (POR)
The POR ensures that the EFM32WG does not start up before the supply voltage V_DD has reached
the threshold voltage VPORthr (see Device Datasheet Electrical Characteristics for details). Before the
threshold voltage is reached, the EFM32WG is kept in reset state. The operation of the POR is illustrated
in Figure 9.2 (p. 100) , with the active low POWERONn reset signal. The reason for the “unknown”
region is that the corresponding supply voltage is too low for any reliable operation.
Figure 9.2. RMU Power-on Reset Operation
V
V_DD
VPORt hr
POWERONn Unknown
t im e
9.3.3 Brown-Out Detector Reset (BOD)
The EFM32WG has 4 brownout detectors, one for the unregulated 3.0 V power, one for the regulated
internal power, one for Analog Power Domain 0 (AVDD0), and one for Analog Power Domain 1 (AVDD1).
2013-05-08 - Wonder Gecko Family - d0233_Rev0.50
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