Electrical characteristics
Figure 20. HSE oscillator circuit diagram
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HSE oscillator critical gm equation
gmcrit = 2 fHSE2 Rm2Co + C2
Rm: Notional resistance (see crystal specification)
Lm: Notional inductance (see crystal specification)
Cm: Notional capacitance (see crystal specification)
Co: Shunt capacitance (see crystal specification)
CL1 = CL2 = C: Grounded external capacitance
gm » gmcrit
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