10.3 Functional Description
An overview of the high frequency portion of CMU is shown in
Figure 10.1 CMU Overview - High Frequency Portion on page 206
. An
overview of the low frequency portion is shown in
Figure 10.2 CMU Overview - Low Frequency Portion on page 206
. These figures
show the CMU for the largest device in the EFM32 family. Please refer to the Configuration Summary in the Device Datasheet to see
which core, and peripheral modules, and therefore clock connections, are present in a specific device.
HFXO
HFRCO
LFXO
LFRCO
prescaler
CMU_HFPERCLKEN0.I2C0
Timeout
Timeout
Timeout
Timeout
CMU_LFECLKEN0.RTCC
HFPERCLK
I2C0
CMU_HFPERCLKEN0.TIMER0
HFPERCLK
TIMER0
HFCORECLK
CORTEX
CMU_CTRL.HFPERCLKEN
HFCLK
Clock
Gate
EM0
LFECLK
RTCC
LFACLK
CMU_LFBCLKEN0.LEUART0
Clock
Gate
LFBCLK
LEUART0
LFBCLK
Clock
Gate
Clock
Gate
clock
switch
clock
switch
clock
switch
prescaler
prescaler
HFCORECLK
HFPERCLK
PCNTnCLK
PCNTn_S0
WDOG
WDOG_CTRL.CLKSEL
CMU_LFBCLKSEL.LFB
CMU_LFACLKSEL.LFA
CMU_HFPERPRESC.PRESC
CMU_HFCOREPRESC.PRESC
CMU_LFBPRESC0.LEUART0
CMU_PCNTCTRL.PCNTnCLKSEL
Debug Trace
Timeout
AUXCLK
WDOGCLK
CMU_HFCLKSEL.HF
clock
switch
CMU_DBGCLKSEL.DBG
prescaler
CMU_HFPRESC.PRESC
HFCLKLE
CMU_LFACLKEN0.LETIMER0
Clock
Gate
LFACLK
LETIMER0
prescaler
CMU_LFAPRESC0.LETIMER0
HFBUSCLK
DMEM
CMU_HFBUSCLKEN0.GPIO
HFBUSCLK
GPIO
Clock
Gate
HFBUSCLK
HFBUSCLK
BUSMATRIX
Prescaler
( /2, /4 )
CMU_HFPRESC.HFCLKLEPRESC
HFSRCCLK
prescaler
HFEXPCLK
CMU_HFEXPPRESC.PRESC
HFBUSCLK
DMA
CMU_HFBUSCLKEN0.DMA
Clock
Gate
DBGCLK
HFBUSCLK
LE
CMU_HFBUSCLKEN0.LE
Clock
Gate
ULFRCO
CRYOTIMER
CRYOTIMER_CTRL.OSCSEL
CRYOCLK
MSC
(Flash Programming)
AUX
HFRCO
HFXO
HFSRCCLK
Clock
Gate
LFECLK
clock
switch
CMU_LFELKSEL.LFE
xor
CMU_ADCCTRL.ADCCLKINV
CMU_ADCCTRL.ADCCLKSEL
ADC_CLK
ADC
HFPERCLK
ADCn
ADCCLKMODE
Availability of oscillators and clocks in Energy Modes:
· Available in EM0/EM1
· Available in EM0/EM1/EM2
· Available in EM0/EM1/EM2/EM3
· Available in EM0/EM1/EM2/EM3/EM4H
· Available in EM0/EM1/EM2/EM4H/EM4S
· Available in EM0/EM1/EM2/EM3/EM4H/EM4S
Figure 10.1. CMU Overview - High Frequency Portion
EFM32JG1 Reference Manual
CMU - Clock Management Unit
silabs.com
| Smart. Connected. Energy-friendly.
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