Information

OSC MCG SIM
Multiplexers MCG_Cx MCG_Cx SIM_SOPT1, SIM_SOPT2
Dividers — MCG_Cx SIM_CLKDIVx
Clock gates OSC_CR MCG_C1 SIM_SCGCx
32 kHz IRC
PLL
FLL
MCGOUTCLK
MCGPLLCLK
MCG
MCGFLLCLK
OUTDIV1
Core / system clocks
4 MHz IRC
OUTDIV4
Flash clock
OUTDIV2
Bus clock
RTC oscillator
EXTAL32
XTAL32
EXTAL0
XTAL0
System oscillator
SIM
FRDIV
MCGIRCLK
ERCLK32K
OSC32KCLK
XTAL_CLK
MCGFFCLK
OSCERCLK
OSC
logic
OSC logic
Clock options for
some peripherals
(see note)
MCGFLLCLK
MCGPLLCLK/
Note: See subsequent sections for details on where these clocks are used.
PMC logic
PMC
LPO
OSCCLK
CG
CG
CG
CG
CG
CG — Clock gate
RTC clock
Clock options for some
peripherals (see note)
OUTDIV3
FlexBus clock
CG
Figure 5-1. Clocking diagram
5.4 Clock definitions
The following table describes the clocks in the previous block diagram.
Clock name Description
Core clock MCGOUTCLK divided by OUTDIV1 clocks the ARM Cortex-
M4 core
Table continues on the next page...
Clock definitions
K20 Sub-Family Reference Manual, Rev. 1.1, Dec 2012
164
Preliminary
Freescale Semiconductor, Inc.
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