I am learning to use the ATXMega128A4U and would like to use the internal 32MHz oscillator with an external 32.768kHz crystal. Per the Xmega datasheet:
The Low-frequency Crystal Oscillator is optimized for use with a 32.768 kHz watch crystal. When selecting crystals, load capacitance and crystal’s Equivalent SeriesResistance, ESR must be taken into consideration. Both values are specified by the crystal vendor.
XMEGA oscillator is optimized for very low power consumption, and thus when selecting crystals, see Table 4-3 for maximum ESR recommendations on 9 pF and 12.5 pF crystals.
The Low-frequency Crystal Oscillator provides an internal load capacitance of typical 8.0 pF. Crystals with recommended 8.0 pF load capacitance can be without external capacitors as shown in Figure 4-3.
Crystals specifying load capacitance (CL) higher than 8.0 pF, require external capacitors applied as described in Figure 4-4.
Since my crystal is listed with a Load Capacitance of 20pF, is that the value of capacitors I should use on TOSC1 and TOSC2 pins?
The Low-frequency Crystal Oscillator is optimized for use with a 32.768 kHz watch crystal. When selecting crystals, load capacitance and crystal’s Equivalent SeriesResistance, ESR must be taken into consideration. Both values are specified by the crystal vendor.
XMEGA oscillator is optimized for very low power consumption, and thus when selecting crystals, see Table 4-3 for maximum ESR recommendations on 9 pF and 12.5 pF crystals.
The Low-frequency Crystal Oscillator provides an internal load capacitance of typical 8.0 pF. Crystals with recommended 8.0 pF load capacitance can be without external capacitors as shown in Figure 4-3.
Crystals specifying load capacitance (CL) higher than 8.0 pF, require external capacitors applied as described in Figure 4-4.
Since my crystal is listed with a Load Capacitance of 20pF, is that the value of capacitors I should use on TOSC1 and TOSC2 pins?