40.7.2 Crystal Oscillator

Figure 40-8. Crystal Oscillator Schematic

The crystal must be located as close to the device as possible. Long signal lines may pose too high of a load for the crystal to operate properly and may cause crosstalk to other parts of the system.

Note: Crystal selection must be done using both the crystal data sheet and the crystal oscillator parameters given in the XOSC Electrical Specifications from the Electrical Characteristics chapter.
Table 40-3. Crystal Oscillator Checklist
Signal NameDescriptionRecommended Pin Connection
XINExternal Crystal.

Crystal frequency range is specified in the XOSC Electrical Specifications (XOSC_1 parameter).

C1 Load Capacitor (1,2)
XOUTC2 Load Capacitor (1,2)
Note:
  1. The capacitors must be placed close to the device.
  2. The calculation for crystal load capacitors is provided in the XOSC Electrical Specifications.