Nxp semiconductors, Chapter 4: lpc24xx clocking and power control – NXP Semiconductors LPC24XX UM10237 User Manual
Page 42
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UM10237_4
© NXP B.V. 2009. All rights reserved.
User manual
Rev. 04 — 26 August 2009
42 of 792
NXP Semiconductors
UM10237
Chapter 4: LPC24XX Clocking and power control
Fig 12. Clock generation for the LPC2400
MAIN
OSCILLATOR
INTERNAL
RC
OSCILLATOR
RTC
OSCILLATOR
PLL
WATCHDOG
TIMER
RTC
PRESCALER
REAL-TIME
CLOCK
BYPASS
SYNCHRO-
NIZER
CPU
CLOCK
DIVIDER
PERIPHERAL
CLOCK
GENERATOR
USB BLOCK
ARM7
TDMI-S
ETHERNET
BLOCK
EMC, LCD,
DMA, FAST I/O
VIC
EXTERNAL
ETHERNET
PHY
2 kB BATTERY
RAM
USB
CLOCK
DIVIDER
system
clock
select
(CLKSRCSEL)
WDT
clock
select
(WDTCLKSEL)
RTC
clock
select
(CCR)
USB clock config
(USBCLKCFG)
CPU clock config
(CCLKCFG)
pllclk
CCLK/8
CCLK/6
CCLK/4
CCLK/2
CCLK
PCLK
SEL0[27:26]
PCLK
SEL0[1:0]
PCONP[13]
PCLK
SEL0[19:18]
PCONP[9]
pclk
WDT
pclk
CAN1
pclk
MCI
pclk
SYSCON
pclk
RTC
PCLK
SEL1[1:0]
pclk
BAT_RAM
rtclk
CAN1
PCLK
SEL1[25:24]
PCONP[28]
MCI
PCLK
SEL1[29:28]
SYSTEM
CTRL
other peripherals
see PCLKSEL0/1
25 or
50 MHz
usbclk
(48 MHz)
cclk