NOTE
For the USB FS controller to operate, the minimum system
clock frequency is 20 MHz.
The USB controller also requires a 48 MHz clock. The clock source options are shown
below.
USB 48MHz
USB_CLKIN
SIM_SOPT2[USBSRC]
MCGPCLK
Figure 5-7. USB 48 MHz clock source
5.7.8 LPUART clocking
The LPUART0 and LPUART1 have a selectable clock as shown in the following figure.
UART2 module operates from the bus clock.
NOTE
The chosen clock must remain enabled if the LPUART0 and
LPUART1 is to continue operating in all required low-power
modes.
Module clocks
KL27 Sub-Family Reference Manual , Rev. 5, 01/2016
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Freescale Semiconductor, Inc.