高精度的SMD振蕩器深受智能家居應用的追棒ECS-8FMX-080-T，在比較石英和 MEMS 的頻率與溫度穩定性時。您會看到基于石英貼片晶振的振蕩器遵循 AT 晶體的連續三次曲線，并在 -40°C ~ +85°C 范圍內達到 ±25 ppm，這對于大多數應用來說已經足夠了。

查看 MEMS 圖，它似乎具有更好的頻率與溫度特性，但如果仔細觀察，您會發現該圖顯示了在調整 PLL 分頻比以補償溫度變化時引起的頻率跳躍。這會導致顯著的頻率跳躍，以補償 MEMS 諧振器的顯著頻率漂移（30 ppm/°C 或 3750 ppm -40°C ~ +85°C）

石英在溫度范圍內比 MEMS 更穩定，并提供高“Q”性能?；谑⒌恼袷幤鞑恍枰捎脺囟妊a償來在所需溫度范圍內保持低至 ±10 ppm 的穩定性。如果需要更好的穩定性，您可以向石英晶體振蕩器添加溫度補償，并在整個溫度范圍內獲得低至 0.5 ppm 的穩定性。

When comparing the Frequency vs. Temperature stability of quartz and MEMS. You see that the quartz-based oscillator follows the continuous cubic curve of an AT crystal and achieves ±25 ppm from -40°C ~ +85°C, which is good enough for most applications.

Looking at the MEMS plot it appears to have better frequency vs. temperature characteristics, but if you look closely you can see that the plot shows frequency jumps caused when the PLL division ratio is adjusted to compensate for changes in temperature. This causes significant Frequency jumps in order to compensate for the considerable frequency drift of the MEMS resonator (30 ppm/°C or 3750 ppm -40°C ~ +85°C)

Quartz is much more stable over temperature than MEMS and offers high “Q” performance. The quartz-based oscillator does not need to employ temperature compensation to maintain stabilities as low as ±10 ppm over the required temperature range. If better stabilities are required, you can add temperature compensation to a quartz oscillator and get stabilities as low as 0.5 ppm over temperature.

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