31.4.2 32.768 kHz Crystal Oscillator

The Clock Generator integrates a low-power 32.768 kHz crystal oscillator. To use this oscillator, the XIN32 and XOUT32 pins must be connected to a 32.768 kHz crystal. Refer to the section “Electrical Characteristics” for appropriate loading capacitor selection on XIN32 and XOUT32.

Note that the user is not obliged to use the 32.768 kHz crystal oscillator and can use the 64 kHz (typical) RC oscillator instead.

The 32.768 kHz crystal oscillator provides a more accurate frequency than the 64 kHz (typical) RC oscillator.

To select the 32.768 kHz crystal oscillator as the source of TD_SLCK, SCKC_CR.OSCSEL must be set. This results in a sequence which enables the 32.768 kHz crystal oscillator. The switch of the TD_SLCK source is glitch-free.