求教关于DFT的preview_dft的错误问题

sunilrirt

Thanks....

i0977454522

An XTAL is an electromechanical resonator that resonates
at its natural frequency when excited with electrical energy.
Fig. 1(a) shows a conventional XTAL oscillator circuit. The
equivalent circuit of an XTAL consists of a series RLC circuit
with a parasitic parallel capacitor Cp. The frequency of oscillation
is mainly determined by the motional inductor Lm and
capacitor Cm. The ESR is the energy dissipating component of
the XTAL. The inverting amplifier provides the negative resistance
that overcomes the loss from ESR and pumps energy
into the XTAL, making it oscillate at its natural frequency.
The output frequency of the XTAL oscillator is very precise,
and its stability is usually specified at parts per million or
per billion (ppm/ppb). The extremely precise output frequency
of XTAL oscillators makes them a natural choice for implementing
clocks. Further, the frequency of oscillation is largely
independent of voltage and process variation.

fangwang85

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