57.4.6 3 to 20 MHz Crystal Oscillator Characteristics

Table 57-22. 3 to 20 MHz Crystal Oscillator Characteristics
SymbolParameterConditionsMin.Typ.Max.Unit
fOSCOperating FrequencyNormal mode with crystal320MHz
tSTARTStartup Time3 MHz, CSHUNT = 3 pF40ms
12 MHz, CSHUNT = 7 pF with CM = 1.6 fF6ms
20 MHz, CSHUNT = 7 pF with CM = 1.6 fF5.7ms
IDDONCurrent Consumption (on VDDIO)3 MHz230µA
12 MHz390µA
20 MHz450µA
CLInternal Equivalent Load CapacitanceIntegrated Load Capacitance7.5910.5pF
(XIN and XOUT in series)
Figure 57-10. 3 to 20 MHz Crystal Oscillator Schematics

CLEXT = 2 × (CCRYSTAL – CL – CPCB)

where, CPCB is the capacitance of the printed circuit board (PCB) track layout from the crystal to the pin.