Running KL03 without an Xtal OSC

[tedmawson]

I'm trying to use a MKL03Z32CAF4R without a crystal.  The KSDK doumentation says "MCG uses the OSC as an external reference clock source." Does this mean is can use it as a reference of it needs it as a reference?

If it IS OK to run MCG lite without any OSC, what accuracy will I get asking for 2 MHz clock from it?

[dereksnell]

Hi Ted,

Yes, you can use the internal oscillators to clock the MCU without needing an external crystal.  Below is the Clocking Diagram of the MCU from the KL03 reference manual.

And the datasheet contains the accuracy of the internal oscillators.  See the snipped below for the 2MHz IRC.