FOX CRYSTAL原厂编码表

FOX CRYSTAL原厂编码表，美国FOX公司是一家创新兼并成长型的晶振品牌，通过不断打磨自身的产品，使得其的价值不断放大，随着在晶体行业的积累，如今对于石英晶振产品的积累已是极其深厚，致力于为用户提供高质量的产品为主，同时也提供适合用户需求的解决方案。

超声波浴是清洁电子元件和印刷电路的常用方法板（PCB）。

这种方法使用超声波和溶剂通过产生空化气泡来清洁物品，空化气泡由高频压力（声波）搅动清洁液，迫使污染物被去除。

超声波是超出人类正常听力范围的声音，典型的浴缸工作频率约为40kHz尽管其它频率设备是可用的。
现代超声波清洗浴可能具有改变浴频率的设施，这是有用的，因为它可能通过上下扫频来减少自谐振，从而有助于减轻可以在一个特定频率创建。
到目前为止，很少有人对石英元件的超声波清洗进行研究。唯一英国赫斯特研究中心的GEC Marconi公布了普遍可用的背景信息1992年，题为《超声波清洗对器件退化的影响——石英晶体器件》。这个该报告的作者在结论的基调上出人意料地乐观，尽管他们发现了许多失败之处即使在它们的小样本量中也是如此。低成本高体积石英的失效率明显更高设备。然而，如果考虑这份报告，重要的是要认识到石英晶体制造业在这中间的几年里发生了巨大的变化。现代的尺寸、包装和安装结构陶瓷包装无法与本报告中分析的金属罐包装相比，此外如今，低成本、大批量生产的总体质量控制与1992年大不相同。

一般来说，MHz范围内的晶体（使用AT切割石英坯）应能在超声波清洗过程未受伤害。尽管必须考虑整体频率和规格
因为较高的频率使用较薄的石英坯料，石英坯料比较厚的低频器件。
然而，使用“音叉”技术产生低频的晶体Quartz crystal，如常见的32.768kHz手表水晶的风险要高得多。在它们的应用中，这些晶体被设计为在非常低的温度下工作驱动电平，这些晶体的内部结构被设计为用非常低的输入功率激发共振级别，这意味着更高的功率级别比其他产品更容易造成物理损伤。这个超声波中使用的频率也更接近石英的共振频率，进一步增加自我共振的可能性。FOX CRYSTAL原厂编码表

从以上几点可以看出，在含有石英产品的PCB上使用超声波清洁是并非没有风险。对于低频晶体，在kHz范围内，FOX不建议使用超声波清洁。对于其他类型的晶体，我们建议在用于生产。

The use of an ultrasonic-bath is a common method of cleaning electronic components and printed circuit boards (PCBs). This method uses ultrasound and a solvent to clean items by creating cavitation bubbles which are produced by high frequency pressure (sound) waves to agitate the cleaning liquid, forcing contamination to be removed. 

Ultrasound is sound beyond the normal hearing range of humans with a typical bath operating around 40kHz although other frequency equipment is available. 

Modern ultrasonic cleaning baths may have the facility to alter the bath frequency and this is useful as it may help to reduce self-resonance by sweeping the frequency up and down thus helping to alleviate damage that may be created at one specific frequency. 

To date, little research on the use of ultrasonic cleaning of quartz components has been done. The only generally available background information was published by GEC-Marconi, Hirst Research Centre in England in 1992 and titled The Effects of Ultrasonic Cleaning on Device Degradation — Quartz Crystal Devices. The authors of the report are surprisingly optimistic in the tone of their conclusions, despite finding many failures even in their small sample size. Failures were found to be significantly higher in low cost high volume quartz devices. However if considering this report, it is important to recognise that quartz crystal manufacturing has changed very dramatically in the intervening years. The size, packaging and mounting structure of modern ceramic packages are not comparable to the metal can packages analysed in this report, additionally the general quality control of low cost high volume manufacturing is very different today than in 1992.

As a general comment, crystals in the MHz range (which use AT cut quartz blanks), should survive an ultrasonic cleaned process unharmed. Although the overall frequency and specification must be taken into account because higher frequencies use thinner quartz blanks which are more susceptible to breakage than thicker lower frequency devices. 

However, crystals that use ‘tuning-fork’ technology to produce low frequencies such as the common 32.768kHz watch crystals are significantly higher risk. In their application these crystals are designed to work at very low drive levels, the internal architecture of these crystals is designed to excite resonance with very low input power levels, meaning higher power levels can cause physical damage more easily than other products. The frequencies used in ultrasonic are also much closer to the resonant frequency of the quartz, further increasing the likelihood of self-resonance. 

With the above points it can be seen that the use of ultrasonic cleaning on PCB’s containing quartz products is not without risks. For low frequency crystals, in the kHz range, FOX do not recommend the use of ultrasonic cleaning. For other crystal types we recommend that experimentation is undertaken to assess the risk before use in production. 

If you are considering using ultrasonic cleaning in your production process then we would recommend that some experimentation is undertaken working with the specific vibration frequencies and energy levels that the components will see in your cleaning equipment to prove suitability. We also recommend that the specific crystal to be used on the PCB is used in the assessment experimentation.

The Institute for Interconnecting and Packaging Electronic Circuits (IPC) paper IPC-TM-650, titled Test to Determine Sensitivity of Electronic Components to Ultrasonic Energy, this provides a good starting point for any experimentation.