GD32W51x User Manual
154
Figure 6-2. Clock tree
20-52 MHz
HXTAL
16 MHz
IRC16M
Clock
Monit or
CK_IRC16M
CK_HXTAL
CK_PLLP
CK_SYS
180 MHz max
AHB
Prescaler
÷
1,2...512
CK_AHB
180 MHz max
APB1
Prescaler
÷
4,8,16
TIMER1,2,3,4,5
CK_APB1 x1
x2 or x4
APB2
Prescaler
÷
2,4,8,16
TIMER0,15,16
CK_APB2 x1
x2 or x4
ADC
Prescaler
÷5,6,10,20
CK_APB2
90 MHz max
Peripheral enable
PCLK2
to APB2 peripherals
CK_APB1
45 MHz max
Peripheral enable
PCLK1
to APB1 peripherals
TIMERx enable
CK_TIMERx
to TIMER0,15,16
TIMERx enable
CK_TIMERx
to TIMER1,2,3,4,
5
CK_ADC to ADC
35 MHz max
AHB enable
HCLK
(to AHB bus,Cortex-
M33,SRAM,DMA,peripherals)
÷8
CK_CST
(to Cortex-M33 SysTick)
FCLK
(free running clock)
32.768 KHz
LXTAL OSC
11
10
01
32 KHz
IRC32K
CK_RTC
CK_FWDGT
(to RTC)
(to FWDGT)
/2 to /32
CK_OUT0
SCS[1:0]
RTCSRC[1:0]
CK_PLLP
CK_HXTAL
CK_IRC16M
CK_LXTAL
11
00
01
10
CKOUT0SEL[1:0]
CKOUT0DIV
÷
1,2,3,4,5
xN
VCO
PLL
180 MHz max
180 MHz max
00
01
10
CK_HPDFAU
DIO
to HPDFAUDIO
Peripheral enable
CK_OUT1
CK_PLLDIG
CK_HXTAL
CK_SYS
CK_PLLI2S
11
00
01
10
CKOUT1SEL[1:0]
CKOUT1DIV
÷
1,2,3,4,5
CK_HXTAL
to USBFS/TRNG
Peripheral enable
0
1
USBFSSEL
/PSC
0
1
PLLSEL
IRC16
MDI V
11
/PLLP
/DIGFS
YSDI V
CK_PLLDIG
/USBFSDI V
to SDIO
Peripheral enable
SDIO SEL
/SDIODI V
xN
VCO
PLLDIG
xN
VCO
PLLI2S
/PLLI2SDIV
/PLLFI
2SDIV
CK_IRC16M
HPDFAUDIOS
EL[1:0]
00
01
10
11
I2SSEL[1:0]
00
01
10
CK_I2S
to I2S
Peripheral enable
0
1
HPDFSEL
CK_APB2
CK_SYS
CK_HPDF
to HPDF
Peripheral enable
CK_USART0
00
USART0SEL[1:0]
01
10
11
CK_LXTAL
CK_IRC16M
CK_I2C0
00
I2C0SEL[1:0]
01
1x
CK_APB1
CK_SYS
CK_USART2
00
USART2SEL[1:0]
01
10
11
CK_LXTAL
CK_IRC16M
CK_APB2
CK_SYS
to USART0
to USART2
CK_SYS
RFDI V
Peripheral enable
Peripheral enable
Peripheral enable
CK160_WIFI
to WIFI11N
to WIFI11N
CK80_WIFI
CK44DSM_WIFI
CK_SDIO
CK40_WIFI
to WIFI11N
to WIFI11N
Peripheral enable
÷2
÷4
÷3.6
CK_APB1
CK_IRC16M
FMC
00
01
10
11
CK_IRC16M
CK_HXTAL
/PLLI2
SPSC
ADC
Prescaler
÷2,4,6,8
0
1
ADCCK[2]