36.5.2 Crystal Oscillator

Figure 36-6. Crystal Oscillator Example Schematic

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

Table 36-5. Crystal Oscillator Checklist
Signal NameRecommended Pin ConnectionDescription
XINLoad capacitor CLEXT(1)(2)External crystal between 0.4 to 32 MHz
XOUTLoad capacitor CLEXT(1)(2)
  1. Use the equation in Crystal Oscillator Characteristics to calculate CLEXT.
  2. Decoupling capacitor should be placed close to the device for each supply pin pair in the signal group.