美国福克斯有源晶振

美国福克斯有源晶振，对于未来充满无线希望的FOX福克斯晶振公司，总是能凭借着自身对于行业的见解，以及对于用户需求深入的洞察，针对性开发系列适合目前市场发展的产品，其中最为主流的产品当属石英晶振，有源晶振，温补晶振，石英晶体振荡器等产品，凭借精湛的工艺，优良的品质使得福克斯产品得到市场一直好评，同时也迎来FOX公司的高光时刻。

福克斯品牌成立于1979年，是生产创新频率控制技术的全球领导者。Fox通过创造尖端产品来提高石英晶体和时钟振荡器的性能、精度、可靠性和稳定性，以满足关键的客户设计和产品需求为荣。Fox由Abracon提供支持，Abracon提供最新的技术设计支持和全球供应链灵活性，以解决客户当今面临的独特挑战。

Founded in 1979, the Fox brand is a global leader in producing innovative frequency control technology. Fox takes pride in meeting critical customer design and product needs by creating cutting-edge products that improve quartz crystal and clock oscillator performance, precision, reliability and stability. Fox is powered by Abracon, which provides the latest technical design support and global supply chain flexibility to solve customers’ unique challenges of today.

FOX已经确定，要精确测量晶体振荡器在1皮秒或以下的抖动，目前唯一可用的方法是测量相位噪声并计算RMS抖动。参阅我们的应用说明“低抖动应用的有源晶体振荡器”以获得完整的解释。在测量晶体振荡器的相位噪声时，我们使用双源法。这导致在与载波的特定偏移频率范围上对1Hz带宽中的相位进行单边带测量。单边带相位噪声结果然后通过特定的频带，通常为10Hz至1MHz或12kHz至20MHz，具体取决于应用。SONET要求的带宽为12 kHz到20 MHz。然后，以dBc/Hz为单位的频域积分相位噪声被转换为以皮秒为单位的时域RMS抖动。在FOX振荡器中，RMS抖动具有随机高斯分布，因为没有使用锁相环。这导致了离散杂散和多峰非高斯分布的缺乏。因此，当由低噪声功率供电时，几乎没有或根本没有确定性抖动供给当抖动具有高斯响应时，RMS抖动是标准偏差或西格玛值。

Fox进口有源晶振中使用的晶体具有非常高的Q值。加载Q值振荡器谐振器环路在10000到100000之间。当振荡器级产生信号、频率可以位于振荡带宽内的任何位置。然而Q谐振器实现了窄的振荡带宽，可以制造具有非常低抖动的振荡器。

The crystals used in the Foxs oscillators have a very high Q value. The loaded Q value of the oscillator resonator loop is between 10,000 to over 100,000. When the oscillator stage generates the signal, the frequency can reside anywhere within the oscillating bandwidth. However, with high Q resonators achieving a narrow oscillation bandwidth, oscillators with very low jitter can be manufactured.

利用Fox振荡器抖动的高斯分布，周期的平均值为在高斯曲线的中心。标准偏差（1西格玛）定义为包含发生的总振荡的68.26%。此窗口位于意思是1西格玛（标准偏差）值是振荡器输出信号的RMS抖动。像标准偏差的数量从平均值增加，SMD振荡器产生该周期偏差的信号的机会大大减少。在7西格玛的情况下，机会是100-1x10-12%，以便发生振荡。在14.069西格玛时，概率为1:1012。FIBRE信道规范要求14西格玛可靠性。美国福克斯有源晶振.
With the Gaussian distribution of jitter of the Foxoscillators, the Mean value of the period is in the center of the Gaussian curve. Standard Deviation (1 sigma) is defined as the window that contains 68.26% of the total oscillation that occurs. This window is placed on one side of the mean. The 1 sigma (Standard Deviation) value is the RMS jitter of the oscillator output signal. As the number of Standard Deviations increases, from the Mean, the chance of the oscillator producing a signal of that period deviation is greatly reduced. At 7 sigma off-set, the chances are 100-1 x10-12 % for oscillation to occur. At 14.069 sigma, the probability is 1:1012. FIBRE Channel specifications requires 14 sigma reliability. 

确定峰-峰（Pk到Pk）值取决于期望的可靠性。可靠性越高Pk到Pk值越大，即使出现的概率随着西格玛值的升高而大大降低。在14西格玛时，概率接近1:1012。这被认为是我们用来根据RMS抖动值确定Pk到Pk抖动的标准。如果Fox振荡器具有2皮秒RMS抖动，Pk到Pk的抖动是28皮秒。这也被认为是总抖动（TJ），因为缺乏1:108 11.224 1:109 11.996 1:1010 12.723 1:1011 13.412 1:1012 14.069 1:1013 14.698 1:1014 15.301 1:1015 15.883 1:1016 16.444

Determining the Peak to Peak (Pk to Pk) value depends on the reliability that is desired. The more reliability
desired, the greater the Pk to Pk value even though the probability of occurrences greatly reduces with higher sigma values. At 14 sigma, the probability is near 1:1012. This is considered the standard we use to determine the Pk to Pk jitter from the RMS jitter value. If a Fox oscillator has a 2 picoseconds RMS jitter,
the Pk to Pk jitter is 28 Fox. This is also considered the Total Jitter (TJ) due to the lack of  The following chart shows other sigma off-sets
required for various probabilities:
Probability SigmaThe following chart shows other sigma off-sets
required for various probabilities:
Probability Sigma
1:108
11.224
1:109
11.996 1:1010
 12.723 1:1011
13.412 1:1012 14.069 1:1013
 14.698
1:1014
 15.301 1:1015
 15.883 1:1016
16.444