Data Sheet

NUC123
May 3, 2017 Page 37 of 99 Rev.2.04
NUC123 SERIES DATASHEET
1. LIRC (10 kHz OSC) ON or OFF depends on Software setting in run mode.
2. If TIMER clock source is selected as LIRC and LIRC is on.
3. If WDT clock source is selected as LIRC and LIRC is on.
Normal Mode
Idle Mode
Power-Down Mode
HXT (4~20 MHz XTL)
ON
ON
Halt
HIRC (12/16 MHz OSC)
ON
ON
Halt
LIRC (10 kHz OSC)
ON
ON
ON/OFF
1
PLL
ON
ON
Halt
LDO
ON
ON
ON
CPU
ON
Halt
Halt
HCLK/PCLK
ON
ON
Halt
SRAM retention
ON
ON
ON
FLASH
ON
ON
Halt
GPIO
ON
ON
Halt
PDMA
ON
ON
Halt
TIMER
ON
ON
ON/OFF
2
PWM
ON
ON
Halt
WDT
ON
ON
ON/OFF
3
WWDT
ON
ON
Halt
UART
ON
ON
Halt
PS/2
ON
ON
Halt
I
2
C
ON
ON
Halt
SPI
ON
ON
Halt
I
2
S
ON
ON
Halt
USB
ON
ON
Halt
ADC
ON
ON
Halt
Table 6-3 Clocks in Power Modes
Wake-up sources in Power-down mode:
WDT, I²C, Timer, UART, BOD, GPIO and USB
After chip enters power down, the following wake-up sources can wake chip up to normal mode.
Wake-Up
Source
Wake-Up Condition
System Can Enter Power-Down Mode Again Condition*
BOD
Brown-Out Detector Interrupt
After software writes 1 to clear BOD_INTF (BODCR[4]).
GPIO
GPIO Interrupt
After software write 1 to clear the ISRC[n] bit.
TIMER
Timer Interrupt
After software writes 1 to clear TWF (TISRx[1]) and TIF (TISRx[0]).