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NUC126
Aug. 08, 2018
Page
82
of 943
Rev 1.03
NUC12
6 S
E
RI
E
S
T
E
CH
NI
CA
L R
E
F
E
RE
NCE
MA
NUA
L
Address match
After software writes 1 to clear WKAKDONE (UI2C_PROTSTS[16], then writes 1
to clear WKF (UI2C_WKSTS[0]).
USCI SPI
SS Toggle
After software writes 1 to clear WKF (USPI_WKSTS[0]).
I
2
C
Address match wake-up
After software writes 1 to clear WKAKDONE (I2C_WKSTS[1]). Then software
writes 1 to clear WKIF(I2C_WKSTS[0]).
USBD
Remote Wake-up
After software writes 1 to clear BUSIF (USBD_INTSTS[0]).
ACMP
Comparator Power-Down
Wake-Up Interrupt
After software writes 1 to clear WKIF0 (ACMP_STATUS[8]) and WKIF1
(ACMP_STATUS[9]).
Table 6.2-4 Condition of Entering Power-down Mode Again
6.2.4
System Power Distribution
In this chip, power distribution is divided into four segments:
Analog power from AV
DD
and AV
SS
provides the power for analog components operation.
The V
REF
should be connected with an external 1uF capacitor that should be located close
to the V
REF
pin to avoid power noise for analog applications.
Digital power from V
DD
and V
SS
supplies the power to the internal regulator which provides
a fixed 1.8 V power for digital operation and I/O pins.
USB transceiver power from V
BUS
offers the power for operating the USB transceiver.
RTC power from V
BAT
provides the power for RTC.
A dedicated power from V
DDIO
supplies the power for PE.8 ~ PE.13.
The outputs of internal voltage regulators, LDO and VDD33, require an external capacitor which
should be located close to the corresponding pin. Analog power (AV
DD
) should be the same voltage
level of the digital power (V
DD
). Figure 6.2-7 shows the power distribution of the NUC126 series.