（图片来源：Sitime）
由于目前电容器的等待时间为一年或更长时间，积压迫使公司延长新设计进入市场的时间表。
据行业专家称，预计短缺在恶化之前会恶化。
有一些预测认为电容器短缺可能会持续到2020年甚至更晚。
有了这样的预测，许多公司正在寻找能够减少电容器依赖性的新策略。
一种解决方案是使用振荡器代替谐振器。
此解决方案还可以解决其他设计问题。
以下是支持用振荡器替换石英晶体谐振器（XTAL）的三个原因，以及为什么这是一个更好的解决方案。
1）谐振器需要负载电容，振荡器则不需要
不需要电容的设计意味着无需等待零件。
大多数谐振器都需要负载电容，以提供相移和持续振荡。
相反，振荡器将具有片上电容的谐振器和振荡器IC组合到一个封装中。
这样做是为了确保谐振器和振荡器电路的匹配，并且不需要用外部电容器调谐谐振频率。
此外，如果使用SiTime 32 kHz MEMS振荡器，则无需电源去耦电容。
（图片来源：SiTime）
2）振荡器需要更少的电路板空间
观察目前最小的晶体谐振器，并考虑到它所需的电容器，所用的总电路板空间超过6 mm2。
与目前可用的最小MEMS振荡器相比，使用的总板空间仅为1.7 mm2。
这有效地将占地面积缩小到不到三分之一的尺寸。
（图片来源：SiTime）
通过使用振荡器可以实现时序占用面积和BOM的进一步减小，因为它是具有输出驱动器的有源电路，其能够根据驱动强度驱动两到三个负载。
因此，单个振荡器可以替换多个晶体以及与之相关的电容器。
3）SiTime的振荡器目前可用
如果没有电容器，这些电容器目前供不应求且交付周期较长，大多数谐振器都是无用的。但是，SiTime MEMS振荡器现在可以在很宽的工作范围内以多种频率，电压和稳定性使用。
虽然使用专用材料和工艺来制造电容器和晶体谐振器等元件，但SiTime MEMS振荡器采用标准半导体封装和工艺制造。
通过利用庞大的半导体行业的基础设施 - 凭借其巨大的容量，众多供应商，许多制造设施和兼容的流程 - 目前已经建立了用于生产硅MEMS振荡器的极其强大的供应链。
此外，SiTime振荡器的架构设计为可编程的。
生产大量空白MEMS振荡器，保存在库存中，并按客户规格进行编程。
因此，制造具有标准工艺和材料的MEMS振荡器，结合其可编程性，可实现极大的灵活性，大规模的可扩展性和超短的交付周期。
目前，Digi-Key Electronics公司提供预编程的SiTime振荡器。
如果希望在实验室中立即对零件进行编程，请使用Time Machine II编程器和一些空白振荡器来创建自定义零件。
通过阅读SiTime的白皮书，可以了解更多关于振荡器的好处：使用振荡器而不是晶体谐振器的八大理由。
以上来自于谷歌翻译
以下为原文
![]() (Image source: SiTime)
With the current wait time for capacitors being a year or more, backlogs are forcing companies to extend timelines for new designs to get to market. According to industry experts, the shortage is expected to worsen before it gets better. There are some predictions that the capacitor shortage may continue to 2020 and possibly later. With a forecast like this, many companies are looking for new strategies that will reduce capacitor dependence. One solution is to use oscillators instead of resonators. This solution could also fix other design issues.
Below are three reasons supporting the replacement of quartz crystal resonators (XTALs) with oscillators and why this is a better solution.
1) Resonators require load capacitors, oscillators don’t
Designs that do not need capacitors means there is no need to wait for parts.
Load capacitors are required in most resonators in order to provide phase shift and sustained oscillation. Conversely, oscillators combine a resonator and an oscillator IC with on-chip capacitance, into one package. This is done to ensure matching of the resonator and oscillator circuit and eliminates the need for tuning the resonate frequency with external capacitors. Additionally, if SiTime 32 kHz MEMS oscillators are used, there is no need for power supply decoupling capacitors.
![]() (Image source: SiTime)
2) Oscillators require less board space
Looking at the smallest crystal resonator currently available and taking into account the capacitors that it requires, the total board space used is in excess of 6 mm2. Contrasting that with the smallest MEMS oscillator currently available, a total of only 1.7 mm2 of board space is used. This effectively shrinks the footprint to less than one-third the size.
![]() (Image source: SiTime)
Further reduction of the timing footprint and BOM can be achieved with the use of an oscillator because of the fact that it is an active circuit with an output driver that is capable of driving two to three loads depending on the drive strength. Because of this, a single oscillator can replace multiple crystals along with the capacitors associated with them.
3) Oscillators from SiTime are currently available
Without capacitors, which are currently in short supply and have long lead times, most resonators are useless. However, SiTime MEMS oscillators are available now in many frequencies, voltages, and stabilities within a wide operating range.
While specialized materials and processes are used to manufacture components such as capacitors and crystal resonators, SiTime MEMS oscillators are manufactured using standard semiconductor packaging and processes. By leveraging the infrastructure of the huge semiconductor industry – with its immense capacity, a multitude of vendors, many fabrication facilities, and compatible processes – an extremely robust supply chain for producing silicon MEMS oscillators is currently in place.
Furthermore, the architecture of SiTime oscillators is designed to be programmable. Large volumes of blank MEMS oscillators are produced, held in inventory, and are programmed to customer specifications. Therefore, manufacturing MEMS oscillators with standard processes and materials, combined with their programmability, results in enormous flexibility, massive scalability, and ultra-short lead times.
Pre-programmed SiTime oscillators are currently available at Digi-Key Electronics today. If the desire is to instantly program parts in the lab, get a Time Machine II programmer and some blank oscillators to create custom parts.
More can be learned about the benefits of oscillators by reading SiTime’s white paper: The top 8 reasons to use an oscillator instead of a crystal resonator.
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