- [行业新闻]Analyze the aging of quartz crystal2019年10月31日 11:50
The 'ageing' of a quartz crystal results in a small change of frequency over time and this effect may have to be taken into account by the customer when designing their circuit depending upon the overall specification that needs to be achieved. There are two main causes of ageing in quartz crystals, one due to mass-transfer and the other due to stress.
Mass-Transfer
Any unwanted contamination inside the device package can transfer material to or from the SMD CRYSTALcausing a change in the mass of the quartz blank which will alter the frequency of the device. For example, the conductive epoxy used to mount the quartz blank can produce 'out-gassing' which can create oxidising material within the otherwise inert atmosphere inside the sealed crystal package and so this production process must be well controlled. Ideally the manufacturing method is as clean as possible to negate any effects and give good ageing results.
Stress
This can occur within various components of the crystal from the processing of the quartz blank, the curing of the epoxy mounting adhesive, the crystal mounting structure and the type of metal electrode material used in the device.Heating and cooling also causes stress due to different expansion coefficients. Stress in the system usually changes over time as the system relaxes and this can cause a change in frequency.
Ageing in practice
When looking at example ageing test results of crystals,it can be seen that the change in frequency is generally greatest in the 1st year and decays away with time. It must be noted however that for example if a device is specified at ±5ppm max per year; it does not follow that the ageing after 5 yrs will be ±5ppm x 5yrs, i.e. ±25ppm. In practice,the example ±5ppm ageing device may be only ±1ppm to ±2ppm in the 1st year of operation and then reduces over subsequent years. It is common to use a general 'guide-rule' for crystal ageing of ±10ppm max over 10 years although in reality it is usually much less than this. It is impossible to predict the exact ageing of a device as even parts made at the same time and from the same batch of quartz will exhibit slightly different ageing characteristics.The production process must be consistent from part to part, from the manufacture of the quartz blank, the electrode size and its placement, to the epoxy used to mount the quartz and its curing thermal profile, all have a slight affect on frequency. Devices can age negatively or positively depending upon the internal causes although parts from one batch tend to follow similar results. Generally the ageing effect is negative in over 90% of parts manufactured.
Accelerated ageing
It is common industry practice to use an accelerated ageing process to predict long term frequency movement by soaking devices at elevated temperatures and measuring frequency movement at relevant intervals. It is normal to test crystals using a passive test (i.e. non-powered). The general rule used is that soaking a crystal at +85℃ for 30 days is equivalent to 1 year of ageing at normal room temperature. If this test is extended for enough time then the recorded data can be plotted graphically to enable via extrapolation, the prediction of future long term ageing.
Frequency adjustment
Note that the ageing of quartz effectively changes the frequency tolerance of the crystal and does not directly influence the stability of the quartz over temperature to any great degree as this parameter is dictated by the 'cut-angle' of the quartz used. If using quartz oscillators that have a voltage-control function such as VCXOs, TCXOs or OCXOs, the output frequency can be adjusted back to its nominally specified value.
Design
The engineer designing a circuit using either a crystal or oscillator will generally know what overall stability figure their equipment must meet over a particular time period.
As the tolerance and/or stability of a device decreases then the more important ageing becomes. For example using a TCXO at ±1ppm stability over temperature will require ageing to be kept to relatively small values. However, if the total frequency movement allowance of a design is for example ±200ppm and a device with a rating of ±100ppm is used then a small amount of ageing can effectively be ignored.
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- [行业新闻]Crystal parameters description2019年10月29日 10:37
About Crystal parameters description,Crystal Project Name
AT Cut Crystals
For precise frequency control in radio and line communication systems, quartz crystal resonators have proved indispensable. The material properties of crystalline quartz are such that quartz resonators display stableness and Q factors that cannot be matched by other types of resonator over the frequency range from 1 MHz to 200 MHz.
Equivalent Circuit
Fig-1 shows the conventionally accepted equivalent circuit of a crystal resonator at a frequency near its main mode of vibration. The inductance LI reiperesents the vibrating mass, the series capacitance CL the compliance of the quartz element and the resistance Rl the internal frication of the element, mechanical losses in the mounting system and acoustical losses to the surrounding environment.
The shunt capacitance Co is made up of the static capacitance between the electrodes, togettier with stray capacitances of the mounting system.
There are two zero-phase frequencies associated with this simple circuit, one is at series resonance fs, another at antiresonance fa. When used in an oscillator, crystal units will operate at any frequency within the broken lines of Fig-2 as determined by the phase of the maintaining circuit.
By changing of this reactive condition, the crystal frequency may be trimmed in a limited extent. The degree to which this frequency may be varied (frequency pulling) is inversely proportional to the capacitance ratio r(C〇 /Ci).
Load Capacitance
Many practical oscillator circuits make use of a load capacitor CL in series or parallel with the crystal, either in order to provide a means for final frequency adjustment, or perhaps for modulation or temperature compensation purposes. For the crystal load capacitance. We looking into the circuit through the two crystal terminals, the load capacitance need to specified when the crystal is paralleled mode, crystal load capacitance is calculated as below:
Frequency Pulling
In many applications a variable capacitor (trimmer) is used as the load reactive element to adjust the frequency. The fractional frequency range available between specified values of this load reactive element is called the pulling range (PR.) and it can be calculated by using the following formula:
Sensitivity
A useful parameter to the design engineer is the pulling sensitivity (S) at a specified value of load capacitance. It is defined as the incremental fractional frequency change for an incremental change in load capacitance. It is normally expressed in ppm/pF (10-6/pF) and can be calculated from the formula:
It is very important to define the mean load capacitance to enable the actual crystal frequency be set within the tolerances of the specified nominal frequency. It is also important to use, wherever possible, standard values of load capacitance; for example:20pF, 30pF.
Fig-3 shows the relationship between LO.; P.R. and S.
Frequency Pulling Calculation
An approximation to the pulling for any crystal can be calculated from this simple formula:
Resistance
The equivalent circuit of the crystal has one other important parameter: This is Ri, the motional resistance. This parameter controls the Q of the crystal unit and will define the level of oscillation in any maintaining circuit. The load resonance for a given crystal unit depends upon the load capacitance with which that unit is intended to operate. The frequency of oscillation is the same in either series or parallel connection of the load capacitance.
If the external capacitance is designated the load resonance resistance may be calculated as follows:
The equivalent shunt or parallel resistance at load resonance frequency is approximately:
It should be remembered that Ri does not change thus the effective parameters of any user network can be readily calculated.
Frequency Temperature Characteristics
The AT-cut crystal has a frequency temperature characteristic which may be described by a cubic function of temperature. This characteristic can be precisely controlled by small variations in the exact angle at which the crystal blank is cut from the original quartz bar. Fig,4 illustrates some typical cases. This cubic behaviour is in contrast to most other crystal cuts, which have parabolic temperature characteristics.
As a consequence, the AT-cut is generally the best choice when specifying a unit to operate over a wide temperature range, and is available in a range of frequencies from 1 to 200 MHz.
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- [技术支持]时钟晶体振荡器的使用与终端设计2019年09月05日 16:50
在当今的高性能系统中,需要一个出色的时钟源。随着专用集成电路(ASIC)的速度和性能达到更高的限制,分配该时钟源以驱动多个设备的需求变得更加困难。由于相关的快速边沿速率,系统中部署的较高频率导致长PCB迹线表现得像传输线。保持平衡系统需要适当的端接技术来实现应用中的跟踪路由。本应用笔记将重点介绍推荐的终止技术;关于输出负载的评论,并提供一些设计师要考虑的布局指南。
传输线理论简介
通常,大多数时钟源具有低阻抗输出。当这些器件用于驱动具有大阻抗的负载时,存在阻抗不匹配。根据应用条件,此阻抗不匹配会导致负载产生电压反射,从而产生时钟波形中的步进,振铃以及过冲和下冲。这可能通过降低负载处的时钟信号,错误的数据时钟和产生更高的系统噪声而导致系统性能不佳。
为了减少电压反射,需要正确终止信号迹线。适当终止的设计考虑因素可以用两个语句来概括:
1.使负载阻抗与线路阻抗相匹配
2.使源阻抗与线路阻抗匹配
对于大多数设计,第一种说法是首选方法,因为它消除了返回时钟源的反射。这样可以减少噪音,电磁干扰(EMI)和射频干扰(RFI)。
下图显示了阻抗不匹配对时钟源的影响
常用终止技术
如上所述,为了减少电压反射,必须正确地终止迹线。 传输线的四种基本端接技术是串联,并联,戴维宁和AC。
系列终止
串联终端消除了时钟源的反射,有助于保持信号质量。 这最适合驱动少量负载的TTL器件,因为时钟输出阻抗小于传输线特性阻抗。 图1显示了一系列终端。 电阻尽可能靠近时钟源放置。 R的典型设计值为10Ω至75Ω。
R的值可以大于阻抗差,以便产生稍微过阻尼的状态并且仍然消除来自时钟源的反射。
系列终端的主要优点是:
1.简单,只需要一个电阻器
2.功耗低
3.在驱动高容性负载时提供电流限制;这还可以通过减少接地反弹来改善抖动性能
系列终止的主要缺点是:
1.增加负载信号的上升和下降时间;这在一些高速应用中可能是不可接受的
2.无法驱动多个负载
平行和戴维宁终结
接下来的三种终端技术可提供更清晰的时钟信号,并消除负载端的反射。这些终端应尽可能靠近负载放置。
图2描绘了并行终端。并联终端消耗的功率最大,不建议用于低功率应用。它也可能改变占空比,因为下降沿将比上升沿更快。它比串联终端具有一个优点,即上升和下降时间的延迟大约是一半。
如图3所示,戴维宁终端将比并联终端消耗更少的功率,并且通常用于PECL应用,50Ω线路匹配至关重要。 R的总值等于传输线的特征阻抗。 如果需要过阻尼状态,则R的总值可略小于特征阻抗。 戴维宁终端的主要缺点是每条线路需要两个电阻器,并且在终端附近需要两个电源电压。 建议不要将此端接用于TTL或CMOS电路。
AC终止
AC端接,如图4所示,在并联支路中增加了一个串联电容。 由于RC时间常数,电容会增加时钟源的负载和延迟,但在稳态条件下将消耗很少或没有功率。 通常不建议使用此终端,因为它会通过增加传播延迟时间来降低时钟信号的性能。 为了保持有效终止,C L的值不应小于50pF。 较大的C L值将允许时钟边沿的快速转换,但随着电容器值的增加,较高的电流电平将通过,从而导致功耗的增加。 选择大于走线阻抗的R L值,以考虑负载输入阻抗的泄漏。
输出负载简介
应注意不要使时钟源过载。 如果使用单个时钟源来驱动多个负载,则如果总负载超过时钟源的驱动能力,则会发生波形劣化。
过载的一些常见症状是波形削波,对称不平衡,信号幅度减小以及上升和下降时间值的变化。 通常随着时钟频率的增加,源驱动更高负载的能力将降低。 请务必参考时钟源规范以获得最大负载能力。
下图显示了重载对时钟源的影响。
通用时钟输出类型
CTS时钟振荡器设计已经开发出来,具有各种封装选项,输入电压和输出类型。
HCMOS和HCMOS / TTL兼容
今天的CTS设计提供“双兼容”振荡器,它们是能够驱动TTL应用的HCMOS输出类型。 由于转换时间较短,这些设备固有地具有更大的过冲和欠冲。 这可能不适合具有严格EMI要求的旧TTL设计。
CTS生产两种流行的HCMOS / TTL兼容时钟振荡器CB3 / CB3LV和型号636。
下图显示了典型的HCMOS测试负载配置和波形参数。
LVPECL和LVDS
与HCMOS逻辑技术相比,CTS LVPECL和LVDS逻辑输出设计具有许多优势。
LVPECL和LVDS技术从正电源获得其工作功率,从而实现与负载点处的HCMOS逻辑接口的必要兼容性。 这些逻辑输出还具有:
1.降低系统抖动; 由于较小的特征过渡区域
2.上升和下降时间更快
3.提供差分输出; 减少排放至关重要
4.能够直接驱动50Ω传输线
5.降低高频时的电源消耗
CTS Model 635提供两种输出类型的选项。
下图显示了典型的LVPECL和LVDS测试负载配置和波形参数
布局指南
在印刷电路板布局过程中采用良好的设计实践将最小化先前讨论的信号劣化。 PCB设计的一些常见指南是:
1.将时钟源物理定位在尽可能靠近负载的位置
2.限制时钟信号的走线长度
3.不要将时钟信号靠近电路板边缘
4.尽量避免在时钟信号路由中使用过孔。 过孔会改变走线阻抗,从而引起反射。
5.不要在电源和接地层上布设信号走线
6.避免在轨迹中出现直角弯曲,如果可能,请保持直线行程。 如果需要弯曲,请使用两个45°角或使用圆形弯曲(最佳).
7. V CC与时钟源地之间的去耦电容对于降低可能传输到时钟信号的噪声至关重要。 这些电容必须尽可能靠近V CC引脚。
8.为避免串扰,请在多个时钟源和高速开关总线之间保持适当的间隔。
9.差分跟踪路由应尽可能接近,以获得高耦合系数。 路由的长度应相等,以避免阻抗不匹配,从而导致不同的传播延迟时间。
10.使用单个时钟源驱动多个负载时,请考虑拆分路由。 使各个布线长度尽可能相等。
结论
本应用笔记介绍了使用驱动各种负载的时钟源的应用的正确终端技术。 它还概述了用于生成可靠应用程序设计的布局考虑因素 所有这些技术都力求最大限度地减少降低时钟信号的条件,从而导致系统性能不佳。
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- [晶振编码查询]1XTV26000AAD|KDS晶振|株式会社大真空|VCTCXO晶振2019年08月30日 08:39
KDS 晶振即是日本大真空株式会社(DASHINKU CORP),成立于 1951 年,至今已有 50 多年的历史,是全球领先的三大晶振制造商之一,其制造工厂主要分布在日本本土、中国、泰国、印度尼西亚等十多个制造中心,KDS 大真空集团总公司位于日本兵库县加古川,在泰国,印度尼西亚,台湾,中国天津这些大城市均有生产工厂,其中天津工厂是全球晶振行业最大的单体制造工厂,也是全球最大的 TF 型晶振制造工厂.
首先非常的感谢你长期以来对【日本大真空株式会社】,KDS 晶振品牌的支持与厚爱.在此郑重声明,本集团以下简称(KDS)在中国的代理商除了北京中国电子研究院,广州电子研究所,【泰河电子】,香港 KDS办事处,台湾KDS办事处,是正规的代理销售企业,其余地区以及公司,个人所销售的KDS产品均不能保证是原装正品,请你选择正规渠道定制货品.
1XTV26000AAD|KDS晶振|株式会社大真空|VC-TCXO振荡器
Model Name 型号 DSA321SCA Original code 原厂代码 1XTV26000AAD Device Name 产品名称系列 VC-TCXO(压控温补振荡器) Nominal Frequency 标称频率 26 MHZ Supply Voltage 电源电压
2.8V Load Impedance 负载阻抗 (resistance part)(parallel capacitance)
10 kΩ
10 pF
Control Voltage Range 控制电压范围
1.15 V Operating Temperature Range 工作温度范围
-40~+85℃ Storage temperature 储存温度
-40~+852px;word-spacing:-1.5px"="" style="font-size:14px">℃ Current Consumption 电流消耗
1.5 mA Output Level 输出电平
0.8 Vp-p Symmetry 对称性
40/60% Harmonics 谐波
-8 dBc
SIZE 尺寸 3.2*2.5*0.9mm 1XTV26000AAD晶振产品尺寸图
1XTV26000AAD晶振产品电气表
关于1XTV26000AAD压控温补振荡器产品安装的注意事项
1端子A通孔不在底部(安装侧)。
2土地图案布局/金属掩模孔以下土地图案为参考设计。电气特性应满足安装在这片土地上的要求。在测试用地和安装用地不相连的范围内,可以改变接地方式。
对电特性没有任何影响。面罩厚度建议为0.12毫米。包装条件
胶带包装
(1)压花胶带格式及尺寸
(2)卷筒数量:最多2000个/卷
(3)胶带规格
不缺产品。
(4)卷筒规格见图3
包装
产品用防静电袋包装。
*湿度敏感度等级:IPC/JEDEC标准J-STD-033/1级
无需干燥包装,无需重新储存后烘烤。
包装箱
最多10卷/包装箱。但是,在少于10卷的情况下,它由任何盒子容纳。
盒子里的空间用垫子填满了。
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- [行业新闻]村田新产品MEMS谐振器应用指南2019年04月20日 09:04
日本村田新研发出一款MEMS谐振器,尺寸仅有0.9*0.6*0.3mm。实现了现石英晶体谐振器达不到超小尺寸,并且低ESR特性的产品。MEMS谐振器的诞生可代替许多石英晶体谐振器。有很多人就想问了什么是MEMS谐振器?它跟振荡器有什么区别?MEMS谐振器有哪些特点?工作原理有哪些?使用都需要注意一些什么问题?等等一大串的问题就随之而来了。
那么我们将一一把问题给大家回复。
首先,大家肯定是会对日本村田陶瓷晶振制作所研发出的产品有些疑问,什么是MEMS呢?其实MEMS指的是微机电系统(Micro Mlectro Mechanical Systems),这种装置运用了半导体生产工艺技术,具有三维微细结构。除了面对MEMS谐振器还有一种是振荡器,MEMS振荡器跟其它普通石英晶体振荡器是一样的,将振荡用电路也谐振器融为一体的装置。可用科尔皮兹振荡电路之类的普通振荡电路驱动。
WMRAG32K76CS1C00R0谐振器是村田MEMS技术的代表作品。该产品具有体极柢的ESR特性以及极小尺寸封装,这个是目前石英晶体谐振器无法实现的突破。极小的尺寸有助于减小安装面积,通过优化IC增益,实现了低ESR的MEMS谐振器,降低了功耗。也可用于回流焊接,引线键合和传递模型。WMRAG32K76CS1C00R0谐振器具有晶体该有的特性,32.768KHZ标频以及20PPM标准稳定偏差。可在-30~+85度下正常工作。驱动电平在0.2μW以内。当您考虑置换晶体的时候,要注意晶体谐振器和MEMS谐振器的负载电容量值不同。
并且要知道MEMS谐振器与普通石英晶体谐振器的区别。
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- [技术支持]What is frequency at load capacitance?2019年04月16日 10:07
1. Introduction
When ordering crystals for oscillators that are to operate at a frequency f, e.g. 32.768 kHz or 20 MHz, it is usually not sufficient to specify the frequency of operation alone. While the crystals will oscillate at a frequency near their series resonant frequency, the actual frequency of oscillation is usually slightly different from this frequency (being slightly higher in “parallel resonant circuits”).1
So, suppose you have a crystal oscillator circuit and you want to purchase crystals such that when placed in this circuit the oscillation frequency is f. What do you need to tell the crystal manufacturer to accomplish this? Do you need to send a schematic of the oscillator design with all the associated details of its design, e.g. choice of capacitors, resistors, active elements, and strays associated with the layout? Fortunately, the answer is no. In addition to the frequency f, all that is needed is a single number, the load capacitance CL .
2. What is CL ?
Suppose your crystal oscillator operates at the desired frequency f. At that frequency, the crystal has complex impedance Z, and for the purposes of frequency of operation, this is the only property of the crystal that matters. Therefore, to make your oscillator operate at the frequency f, you need crystals that have impedance Z at the frequency f. So, at worst, all you need to specify is a single complex number Z = R+jX. In fact, it is even simpler than this.
While in principal one should specify the crystal resistance R at the frequency f, usually the crystal-to- crystal variation in R and the oscillator’s sensitivity to this variation are sufficiently low that a specification of R is not necessary. This is not to say that the crystal resistance has no effect; it does. We shall discuss this further in Section 4.
So, that leaves a single value to specify: The crystal reactance X at f. So, one could specify a crystal having a reactance of 400 ? at 20 MHz. Instead,however, this is normally done by specifying a capacitance C L and equating.
where we have set ω = 2πf. Physically, at this frequency, the impedance of the series combination of the crystal and a capacitance C L has zero phase (equivalently, has zero reactance or is purely resistive). See Figure 1. To see this, consider
where the second step follows by Equation (1) and the fact that the reactance of a capacitance C is -1/( ωC).
Figure 1—This series combination has zero-phase impedance at a frequency where the crystal has load capacitance CL
So, the task of assuring proper oscillation frequency is the task of providing components (crystals in this case) that, at the specified frequency, have the required reactance, which is stated in terms of a capacitance CL by Equation (1).2 For example, instead of specifying crystals having a reactance of 400 ? at 20 MHz, we specify crystals having a load capacitance of 20 pF at 20 MHz, or more normally, we specify that the crystal frequency be 20 MHz at a load capacitance of 20 pF.
In “parallel resonant circuits,” CL is positive, typically being between 5 pF and 40 pF. In this case the crystal operates in that narrow frequency band between the crystal’s series and parallel resonant frequencies (F s and F p , respectively).
While a truly “series resonant circuit” does not have a load capacitance associated with it [or perhaps an infinite value by Equation (1)], most “series resonant circuits” actually operate slightly off of the series resonant frequency and therefore do have a finite load capacitance (that can be positive or negative).However, if this offset is small and specifying a load capacitance is not desired, it can either be ignored or handled by a slight offset in the specified frequency f.
As we shall see in Section 4, both the oscillator and the crystal determine C L . However, the crystal’s role is rather weak in that in the limit of zero resistance,the crystal plays no role at all in determining C L . In this limiting case, it makes sense to refer to C L as the oscillator load capacitance as it is determined entirely by the oscillator. However, when it comes time to order crystals, one specifies crystals having frequency f at a load capacitance C L , i.e. it is a condition on the crystal’s frequency. Because of this,it would be reasonable to refer to C L as the crystal load capacitance. For the sake of argument, we simply avoid the issue and use the term loadcapacitance.
注释:1> When ordering crystals for series resonant operation,instead of specifying a value for C L , be sure to state that the frequency f refers to the series-resonant frequency, F s .
2> This is not to say that all aspects of frequency determination are tied to this single number. For example,other aspects of the crystal and oscillator determine whether the correct mode of oscillation is selected and the system’s frequency stability (short and long term).
3. Defining F L at C L
We now take Equation (1) as our defining relation for what we mean by a crystal having a given frequency at a given load capacitance.
Definition: A crystal has frequency F L at a load capacitance C L when the reactance X of the crystal at frequency F L is given by Equation (1), where now ω = 2πF L .
Recall that, around a given mode, the reactance of a crystal increases from negative values, through zero at series resonance, to large positive values near parallel resonance where it rapidly decreases to large negative values, and then again it increases towards zero. (See Reference [1].) By excluding a region around parallel resonance, we have a single frequency for each value of reactance. In this way,we can associate a frequency F L given a value of C L .So, positive values of C L correspond to a frequency between series and parallel resonance. Large negative values of C L , correspond to a frequency below series resonance while smaller negative values correspond to frequencies above parallel resonance.(See Equation (3) below.)
3.1. The crystal frequency equation So, how much does the frequency of oscillation depend on the load capacitance C L ? We can answer this question by determining how the crystal frequency F L depends on the crystal load capacitance CL . One can show that to a very good approximation that
where C 1 and C 0 are the motional and static capacitances of the crystal, respectively. (See Reference [1] for a derivation and discussion of this relation.) For the purposes of this note, we shall refer to Equation (3) as the crystal frequency equation.
This shows the dependence of a crystal oscillator’s operational frequency on its load capacitance and its dependence on the crystal itself. In particular, the fractional frequency change when changing the load capacitance from C L1 to C L2 is given to good approximation by
3.2. Trim sensitivity
Equation (3) gives the dependence of operating frequency F L on the load capacitance C L . The negative fractional rate of change of the frequency with C L is known as the trim sensitivity, TS. Using Equation (3), this is approximately
From this we see that the crystal is more sensitive to given change in C L at lower values of C L .
4. But what determines C L ?
Consider the simple Pierce oscillator consisting of a crystal, an amplifier, and gate and drain capacitors as shown in Figure 2.
There are at least three stray capacitances that must be considered in trying to calculate the load capacitance of the Pierce oscillator circuit.
1. An added capacitance from the input of the amplifier to ground. Sources for this could be the amplifier itself and trace capacitance to ground. As this capacitance is in parallel with C G , we can simply absorb this into our definition of C G . (That is C G is the capacitance of the capacitor to ground plus any additional capacitance to ground on this side of the amplifier.)
2. An added capacitance from the output of the amplifier to ground. Sources for this could be the amplifier itself and trace capacitance to ground. As this capacitance is in parallel with C D , we can simply absorb this into our definition of C D . (That is C D is the capacitance of the capacitor to ground plus any additional capacitance to ground on this side of the amplifier.)
3. A stray capacitance C s shunting the crystal as shown in Figure 2.
Redefining C G and C D as discussed above, it then follows [2] that one of the conditions for oscillation is
Where
is the impedance of the parallel combination of the crystal and the capacitance C s and R o is the output resistance of the amplifier.
It can be shown that the crystal resistance R as a function of load capacitance C L is given approximately by (provided C L is not too small)
where R 1 is the motional resistance of the crystal [1].It then follows that (provided C L – C s is not too small)
And
With these results, Equation (6) gives the following equation for C L
where R ′ is approximated by Equation (9). Note that the equation for C L is actually a bit more complicated than it might seem at first as R ′ depends upon on C L.It can be seen that C L decreases as R 1 increases, and so by Equation (3), the frequency of operation increases with crystal resistance. So, the load capacitance does have a dependence on the crystal itself. But as we have mentioned previously, the variation in crystal resistance and resulting sensitivity to this variation is usually sufficiently low that the dependence can be ignored. (In this case, a nominal value for crystal resistance is used in calculating C L .)
However, sometimes the resistance effect cannot be ignored. Two crystals tuned so that both have exactly the same frequency at a given load capacitance C L can oscillate at different frequencies in the same oscillator if their resistances differ. This slight difference leads to an increase in the observed system frequency variation above that due to crystal frequency calibration errors and the board-to-board component variation.
Note that in the case of zero crystal resistance (or at least negligible compared to the output resistance Ro of the amplifier), Equation (11) gives
So, in this case, the load capacitance is the stray capacitance shunting the crystal plus the series capacitance of the two capacitances on each side of the crystal to ground.
5. Measuring CL
While in principal one could calculate C L from the circuit design, an easier method is simply to measure C L . This is also more reliable since it does not rely on the oscillator circuit model, takes into account the strays associated the layout (which can be difficult to estimate), and it takes into account the effect of crystal resistance. Here are two methods for measuring C L .
5.1 Method 1
This method requires an impedance analyzer, but does not require knowledge of the crystal parameters and is independent of the crystal model.
1. Get a crystal that is similar to those that will be ordered, i.e. having similar frequency andresistance.
2. Place this crystal in the oscillator and measurethe frequency of operation F L . In placing the crystal into the circuit, be careful not to damage it or do anything to cause undue frequency shifts.(If soldered in place, allow it to cool down to room temperature.) A good technique that avoids soldering is simply to press the crystal onto the board’s solder pads using, for example,the eraser end of a pencil and observe the oscillation frequency. Just be careful that the crystal makes full contact with the board. The system can still oscillate at a somewhat higher frequency without the crystal making full contact with the board.
3. Using an impedance analyzer, measure the reactance X of the crystal at the frequency F L determined in Step 2.
4. Calculate C L using Equation (1) and the measured values for F L ( ω = 2πF L ) and X at F L .
5.2 Method 2
This method is dependent upon the four-parameter crystal model and requires knowledge of these parameters (through your own measurement or as provided by the crystal manufacturer).
1. Get a crystal that is similar to those that will be ordered, i.e. having similar frequency and resistance.
2. Characterize this crystal. In particular measure its series frequency Fs , motional capacitance C1,and static capacitance C0.
3. Place this crystal in the oscillator and measure the frequency of operation F L (as in Method 1,Step 2.)
4. Calculate C L using Equation (3) and the measured values for F L , F s , C 1 , and C 0 .
It is recommended that either procedure be followed with at least 3 crystals. When done properly, this technique often gives values for C L that are consistent to about 0.1 pF. Further confidence in the final results can be found by repeating the procedure for a number of boards to estimate the board-to-board variation of C L .
Note that in the above, F L does not have to be precisely the desired oscillation frequency f. That is, the calculated value for C L is not a strong function of the oscillation frequency since normally only the crystal is strongly frequency dependent. If, for some reason, the oscillator does have strong frequency dependent elements, then using this procedure would be quite difficult.
6. Do I really need to specify a value for CL ?
There are at least three cases where a specification of C L is not necessary:
1. You intend to operate the crystals at their series-resonant frequency.
2. You can tolerate large errors in frequency (on theorder of 0.1% or more).
3. The load capacitance of your circuit is sufficiently near the standard value (see crystal data sheet) that the frequency difference is tolerable. This difference can be calculated with Equation (4).
If your application does not meet one of the three conditions above, you should strongly consider estimating the load capacitance of your oscillator and use this value in specifying your crystals.
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- [技术支持]什么是三态函数2019年04月01日 14:24
What is Tri-State Function?
トライステート関数とは
1. In oscillator with Tri-state function, oscillator output can be controlled by the Tri-state pin as follows:
Logic High : Output Enable
Logic Low :Output Disable
トライステート機能付きオシレータでは、次のようにトライステートピンでオシレータ出力を制御できます。
ロジックハイ:出力イネーブル
ロジックロー:出力ディセーブル
2. The Tri-state function would allow output pin to assume high-impedance state, effectively removing the oscillator output from the circuit.トライステート機能により、出力ピンをハイインピーダンス状態にすることができ、回路から発振器の出力を効果的に取り除くことができます。
3. Oscillator circuits can remain on or be turned off while output is disabled in Tri-State.
出力がトライステートでディスエーブルされている間、発振回路はオンのままにするかオフにすることができます。
Oscillator Operating Mode in Tri-state:Oscillator Circuits Off
トライステートの発振器動作モード:発振器回路オフ
•Advantage :Lower standby current
•利点:スタンバイ電流が低い
•Drawback :Longer startup time:( Fundamental mode > 0.2mS),( 3rd Overtone mode > 2mS)
•欠点:起動時間が長くなります:(基本モード> 0.2ミリ秒)、(3倍音モード> 2ミリ秒)
Oscillator Operating Mode in Tri-state:Oscillator Circuits On
トライステートのオシレータ動作モード:オシレータ回路オン
•Advantage:Shorter output enable time(< 0.1mS)
利点:短い出力イネーブル時間(<0.1mS)
•Drawback:Higher standby current
欠点:高いスタンバイ電流
Standby Current Comparison between Different Oscillator Operating Mode
異なる発振器動作モード間の待機電流の比較
Standby Current
Supply Voltage(VDD)
1.8V
2.5V
2.8V
3.3V
5V
Oscillator off
22MHz
0.4uA
0.5uA
1.1uA
1.6uA
4.1uA
44MHz
0.4uA
1.5uA
1.7uA
2.3uA
6.1uA
Oscillator on
22MHz
0.33mA
0.5mA
1.16mA
44MHz
2.1mA
3.4mA
13.5mA
•Only PX/PY series have oscillator on/off option when output is disabled.
出力が無効の場合、PX / PYシリーズのみオシレータのオン/オフオプションがあります。
•All other oscillator series have oscillator turned off in Tri-state.
他のすべての発振器シリーズは、トライステートで発振器がオフになっています。
How to Disable Tri-State Function
トライステート機能を無効にする方法
•If Tri-state function is no needed, the Tri-state pin shall be connected to the Vcc pin or left floating.
トライステート機能が不要な場合は、トライステートピンをVccピンに接続するか、フローティングのままにします。
There is a internal pull- up resistor which would enable output if Tri-state pin is left floating.
トライステートピンをフローティングのままにしておくと、出力をイネーブルする内部プルアップ抵抗があります。
•TAITIEN recommends connecting Tri-State pin to VCC if Tri-state function is not needed.
トライステート機能が不要な場合は、トライステート端子をVCCに接続することをお勧めします。
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- [行业新闻]NSK OSCILLATOR数据表2019年03月06日 10:04
- 台湾NSK津绽晶振公司成立于1996年的9月份。成立之后的NSK晶振公司将全部精力投入到石英晶体振荡器,陶瓷滤波器,石英晶体,TCXO振荡器,差分晶振等产品的生产中。NADD 75晶振属于石英晶体振荡器中的一种,也是振荡器里的“贵族”。是差分晶体系列的一员。LVDS输出范围,频率也可以从77.76MHZ到622.08MHZ的高频中。大气化的尺寸7*5*1.9mm可放在任意高端产品中,NADD 75晶振在任何电路板中都显得格外的高端。
NAOD 75 CMOS 1.0 to 125.0 MHz 7*5*1.6 NAOH 53 CMOS 1.0 to 125.0 MHz 5*3.2*1.3 NAOK 32 CMOS 2.0 to 54.0 MHz 3.2*2.5*1.2 NAOL 22 CMOS 2.0 to 50 MHz 2*2.5*0.95 NADD 75
LVDS 77.76 MHz ~ 622.08 MHz 7*5*1.9 NAPD 75
LVPECL 75 MHz ~ 622.08 MHz 7*5*1.9 NAVD-6 CMOS 1.0 MHz to 52.0 MHz 7*5*1.8 NAVH-6 CMOS 12MHz ~ 35.328MHz 5*3.2*1.5 NAOD 75 CMOS 32.768 KHz 7*5*1.6 NAOH 53 CMOS 32.768 KHz 5*3.2*1.5 NAOK 32 CMOS 32.768 KHz 3.2*2.5*1.2 NAON 21
CMOS 2.0 to 50 MHz 2.05*1.65*0.75 - 阅读(185)
- [行业新闻]ECS晶振型号表2019年02月16日 15:42
ECS-.327-12.5-16-TR晶振,ECX-16石英晶振,ECS-.327-12.5-16-C-TR晶振,ECX-16石英晶振,ECS-.327-9-16-TR晶振,ECX-16石英晶振,ECS-.327-9-16-C-TR晶振,ECX-16石英晶振,ECS-.327-7-16-TR晶振,ECX-16石英晶振,ECS-.327-7-16-C-TR晶振,ECX-16石英晶振,ECS-.327-5-16-TR晶振,ECX-16石英晶振,ECS-.327-5-16-C-TR晶振,ECX-16石英晶振,ECS-.327-12.5-12L-TR晶振,ECX-12L石英晶振,ECS-.327-12.5-12L-C-TR晶振,ECX-12L石英晶振,ECS-.327-9-12L-TR晶振,ECX-12L石英晶振,ECS-.327-9-12L-C-TR晶振,ECX-12L石英晶振,ECS-.327-7-12L-TR晶振,ECX-12L石英晶振,ECS-.327-7-12L-C-TR晶振,ECX-12L石英晶振,ECS-.327-6-12L-TR晶振,ECX-12L石英晶振,ECS-.327-6-12L-C-TR晶振,ECX-12L石英晶振,ECS-.327-12.5-12R-TR晶振,ECX-12R石英晶振,ECS-.327-12.5-12R-C-TR晶振,ECX-12R石英晶振,ECS-.327-9-12R-TR晶振,ECX-12R石英晶振,ECS-.327-9-12R-C-TR晶振,ECX-12R石英晶振,ECS-.327-7-12R-TR晶振,ECX-12R石英晶振,ECS-.327-7-12R-C-TR晶振,ECX-12R石英晶振,ECS-.327-6-12R-TR晶振,ECX-12R石英晶振,ECS-.327-6-12R-C-TR晶振,ECX-12R石英晶振,ECS-.327-12.5-34B-TR晶振,ECX-31B石英晶振,ECS-.327-12.5-34B-C-TR晶振,ECX-31B石英晶振,ECS-.327-9-34B-TR晶振,ECX-31B石英晶振,ECS-.327-9-34B-C-TR晶振,ECX-31B石英晶振,ECS-.327-7-34B-TR晶振,ECX-31B石英晶振,ECS-.327-7-34B-C-TR晶振,ECX-31B石英晶振,ECS-.327-12.5-34G-TR晶振,ECX-34G石英晶振,ECS-.327-12.5-34G-C-TR晶振,ECX-34G石英晶振,ECS-.327-6-34G-TR晶振,ECX-34G石英晶振,ECS-.327-6-34G-C-TR晶振,ECX-34G石英晶振,ECS-.327-12.5-34R-TR晶振,ECX-34R石英晶振,ECS-.327-12.5-34R-C-TR晶振,ECX-34R石英晶振,ECS-.327-9-34R-TR晶振,ECX-34R石英晶振,ECS-.327-9-34R-C-TR晶振,ECX-34R石英晶振,ECS-.327-7-34R-TR晶振,ECX-34R石英晶振,ECS-.327-7-34R-C-TR晶振,ECX-34R石英晶振,ECS-.327-12.5-34RR-TR晶振,ECX-34RR石英晶振,ECS-.327-12.5-34RR-C-TR晶振,ECX-34RR石英晶振,ECS-.327-9-34RR-TR晶振,ECX-34RR石英晶振,ECS-.327-9-34RR-C-TR晶振,ECX-34RR石英晶振,ECS-.327-6-34RR-TR晶振,ECX-34RR石英晶振,ECS-.327-6-34RR-C-TR晶振,ECX-34RR石英晶振,
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- [技术支持]低相位噪声低成本定时解决方案2019年01月07日 09:47
当前最先进的通信电路,例如:
•μWave频率上变频器
•点对点μWave回程
•卫星调制解调器
•高端网络
•测试和测量设备
都有一个共同点;极低的相位噪声频率参考.从历史上看,为了达到这种水平的相位噪声,振荡器制造商依靠SC-Cut晶振或第5或第7泛音AT-Cut晶体作为参考振荡器解决方案.
前者产生的OCXO体积庞大,功耗过大而且相当昂贵.后者实施起来很复杂,频率提供有限,并且抑制了系统自动校正老化和温度漂移的能力.
解决成本,尺寸,功率,频率稳定性和长期老化校正的综合挑战;Abracon开发了ABLNO系列VCXO晶振,具有出色的相位噪声特性,采用9x14mm封装.
提供50.0MHz和156.25MHz之间的十五个标准频率;这些器件为设计人员提供了全面的参考时序选择.此外,如果系统要求不能使用电压可控振荡器,ABLNO系列可提供固定时钟配置.
图(1)示出了50MHz载波处的典型相位噪声,而图(2)和(3)分别表示100MHz和156.25MHz载波处的典型相位噪声.表(1)总结了在这些载波上配置为VCXO振荡器的ABLNO系列的典型相位噪声性能,而表(2)表示绝对最差情况下的相位噪声特性.
表格1)
典型的相位噪声性能
表(2)
最差情况保证相位噪声性能
ABLNO系列采用经过特殊处理的第3版Overtone,AT-Strip石英晶体设计,采用各种处理技术进行优化,可在温度范围内提供极高的无负载“Q”和频率稳定性.这些晶体和振荡器电路的组合设计具有同类最佳的相位噪声作为主要目标;在载波的12kHz至20MHz的最佳带宽范围内产生了极低的均方根抖动.
表3)
ABLNO系列rms抖动
为了确保出色的相位噪声性能,ABLNO系列不仅满足上述设计的性能参数,而且Abracon还对100%的产品进行了相位噪声和均方根抖动兼容性的室温测试.
如前所述,Abracon已经制定了专有的Quartz-Blank处理技术,以显着降低这些器件的频率与温度误差.通常,相对于25ºC下的测量频率,ABLNO系列器件的误差小于±12ppm(最大值为±18ppm).在-40ºC至+85ºC的工作温度范围内可确保稳定性,如下图(4)所示.
此外,这些器件在10年的产品寿命期间保证比±7ppm的老化更好.为了在此期间实现频率校正能力,VCXO配置中保证了±28ppm的最小频率牵引能力,见图(5).
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- [常见问题]什么是晶振的具体参数2018年09月10日 15:27
每天都会接到很多晶振客户的询盘,有的是工厂采购,有的是贸易商采购,有的是EMS代工厂采购员等等.每天都有上百个咨询石英晶振参数报价及拿货订货.也有很多客户经常会"一问三不知",什么是一问三不知,就是我们石英晶振销售人员口中经常说的参数,尺寸,封装.并不是每一个来咨询问料的客户都是能很清楚明白的知道晶振都有哪些参数.这也跟专业性有关吧,毕竟我们是专业做晶振这一块的,对于刚接触晶振的采购人员来说就是一个未知领域,就像我一样,我从事石英晶振销售三年有余,虽然说是从事电子行业的人员,但我却对其它电子产品”一概不知”.什么电容电阻二三极管,到现在为止我都还不知道他们到底长啥样.虽然客户发过来的电路板上是会有这些产品出现,但我却认不出来.只能从板子里认出晶振,然后估出大概尺寸,看出哪个品牌.我们公司从事晶振行业18年有余,一直坚守晶振行业这个领域的事业.现在给大家介绍一下<什么是晶振的具体参数>,<晶振的专业术语>.
Every day, I receive a lot of enquiries from crystal customers, some are factory procurement, some are traders, some are EMS foundry buyers, etc. Every day, there are hundreds of consulting quartz crystal parameters and get orders. Many customers often "One question, three don't know", what is one question, three, I don't know, it is the parameters, size, and packaging that we often say in the quartz crystal sales staff. Not every customer who consults can know clearly what crystals are. Parameters. This is also related to professionalism. After all, we are specialized in crystal oscillators. It is an unknown field for purchasers who are just in contact with crystal oscillators. Like me, I have been engaged in the sales of quartz crystal oscillators for more than three years, although I am a person in the electronics industry, but I don’t know about other electronic products. I don’t know what capacitors and diodes are. So far, I don’t know how long they are. Although the customer’s board will be there. These products appear, but I can't recognize them. I can only recognize the crystal oscillator from the board, and then estimate the approximate size to see which brand. Our company is engaged in crystal oscillators. More than 18 years, we remain firmly committed to the cause of the crystal industry in this area and now tell you about
. 首先就是我们经常有问到的,标准频率以及频率偏差也称之为精度.(Nominal Frequency and Tolerance)
The first is what we often ask. Standard frequency and frequency deviation are also called accuracy. (Nominal Frequency and Tolerance)
在正确的振荡线路匹配下,从振荡线路输出的频率称之为”公称频率”.石英晶体谐振器的频率通常都是以兆赫兹(MHZ)或者千赫兹(KHZ)来表示.而频率偏差则是在实际批量生产及振荡线路应用上,产品在室内环境25度中都会有一些相对于中心频率的频率误差.这一类的频率容许误差的最大散布值,一般是有ppm(parts per million)或者%(percent)来表示.
Under the correct oscillating line matching, the frequency output from the oscillating line is called the “nominal frequency.” The frequency of the quartz crystal resonator is usually expressed in megahertz (MHZ) or kilohertz (KHZ). The frequency deviation is In actual mass production and oscillating line applications, the product will have some frequency error relative to the center frequency in the indoor environment of 25 degrees. The maximum dispersion value of this type of frequency tolerance is generally ppm (parts per million). Or %(percent) to indicate.
其次就是石英晶振的基本波振荡和倍频振荡模态简称”泛音振动”. (Fundamental and Overtone Vibrations Mode)
The second is the fundamental wave oscillation of the quartz crystal oscillator and the frequency doubling oscillation mode referred to as "overtone vibration". (Fundamental and Overtone Vibrations Mode)
AT切割型的石英晶振主要以厚度剪切振荡模式存在,高次谐振动波与电极区域之间的基本振动共存.由于两个电极的极性相反,在压电石英晶体谐振器中只能激发奇数谐波振动.
The AT-cut quartz crystal oscillator mainly exists in the thickness shear oscillation mode, and the high-order harmonic vibration wave coexists with the basic vibration between the electrode regions. Since the polarities of the two electrodes are opposite, only the piezoelectric quartz crystal resonator can be excited. Odd harmonic vibration.
再然后就是相当主要的负载电容了(Load capacitance),负载电容CL是振荡器通过谐振器两端观察电路时所呈现出的电容量,负载电容形式上与谐振器串联或者并联,对于并联负载情况,CL的存在将影响并联谐振频率,而并联负载谐振频率FL由下面工式给出,所以在咨询型号参数的时候,这个参数必需是客户指定参数.
Then there is a fairly large load capacitance. The load capacitance CL is the capacitance that the oscillator exhibits when observing the circuit through the resonator. The load capacitance is in series or parallel with the resonator. For parallel load conditions. The presence of CL will affect the parallel resonant frequency, and the parallel load resonant frequency FL is given by the following equation, so when consulting the model parameters, this parameter must be the customer-specified parameter.
在晶振购买过程中,这些参数都是用得较多的几个参数了.其实还有很多参数还没介绍完,明日再继续更新最新的晶振参数说明.希望可以帮助那些想要了解晶振,并且采购晶振的客户去了解更多的信息资料.
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- [新闻中心]石英手表的诞生2018年09月04日 08:58
世界上第一块石英表的实际应用与音叉石英晶振的开发是不少工程师所流下的血液,汗水以及眼泪的结晶.随着时间慢慢的推移,石英晶振产品不断的连接着电视,电脑,手机,手表等慢慢靠近着我们的生活.渐渐的这些石英晶振产品已发展成电子行业不可或缺的固定产品.甚至被称为”工业之盐”,电子产品的”心脏”.这些石英晶振最早主由EPSON TOYOCOM公司生产制作而成.
The practical application of the world's first quartz watch and the development of the tuning fork quartz crystal oscillator are the crystallization of blood, sweat and tears that many engineers shed. As time goes by, quartz crystal products are continuously connected to TVs and computers. Mobile phones, watches, etc. are slowly approaching our lives. Gradually these quartz crystal products have developed into indispensable fixed products for the electronics industry. They are even called "the salt of industry", the "heart" of electronic products. These quartz crystal oscillators The earliest production was produced by EPSON TOYOCOM.
QMEMS(Quartz+”MEMS”)是促进MEMS(微电子机械系统)晶体材料微加工工艺独特技术的名称,是EPSON TOYOCOM公司产品的主要核心技术.通过充分利用这项技术的优势可以为石英晶体器件实现更小巧的尺寸及更好的性能.QMEMS技术的起源可以追溯到20世纪70年代初.
QMEMS (Quartz+ "MEMS") is the name of a unique technology that promotes micromachining of MEMS (micro-electro-mechanical systems) crystal materials. It is the main core technology of EPSON TOYOCOM. By taking advantage of this technology, it can be realized for quartz crystal devices. Smaller size and better performance. The origins of QMEMS technology can be traced back to the early 1970s.
1969年,在日本中部的苏瓦湖岸边,当地的一家公司悄然成功地将世界上第一块石英晶振手表变成了现实 - “精工石英天文35Q”(图1),这一事件让世界措手不及。
In 1969, on the shores of Lake Suva in central Japan, a local company quietly succeeded in turning the world's first quartz watch into reality - "Seiko Quartz Astronomy 35Q" (Figure 1), an event that caught the world off guard. .
这真是一个划时代的突破。在此之前,石英钟表虽然非常精确,但却非常大,以至于不能轻易携带,而是采用箱形钟表的形式悬挂在墙壁上。虽然机械手表当然已经存在,但这些并不精确。需要一个创新的解决方案来解决更好的精度和更紧凑的尺寸的双重问题,全球各地的公司都在1960年代中后期进行无情竞争以找到一个问题。
This is really an epoch-making breakthrough. Prior to this, quartz clocks, although very precise, were so large that they could not be easily carried, but were suspended from the wall in the form of a box-shaped clock. Although mechanical watches certainly exist, these are not precise. An innovative solution is needed to solve the double problem of better precision and more compact size, and companies around the world have ruthlessly competed in the mid to late 1960s to find a problem.
图1:世界上第一块石英手表'精工石英Astron 35Q'
注:这些电影是使用YouTube™提供的。
YouTube是Google Inc.的商标
图2:Quartz Astron开发之前的晶体单元这是222222;="" mso-ansi-language:en-us;mso-fareast-language:zh-cn;mso-bidi-language:ar-sa"="" style="font-size:12px">
在Quartz Astron到来之前实际使用的晶体单元222222;="" mso-ansi-language:en-us;mso-fareast-language:zh-cn;mso-bidi-language:ar-sa"="" style="font-size:12px">
类型的一个例子。虽然看起来很大,长约50毫222222;mso-ansi-language:en-us;mso-fareast-language:zh-cn;mso-bidi-language:="" ar-sa"="" style="font-size:12px">
米,但它实际上是当时最小的水晶单元之一.它是精工苏瓦株式会社,苏瓦湖岸边,它正悄悄地控制着这个发展的竞争对手。使精工苏瓦株式会社领先其竞争对手的因素之一是该公司成功地使晶体单元更加紧凑。传统的水晶装置尺寸非常大,无法装入手表般小的东西(图2)。精工苏瓦株式会社通过采用称为“音叉晶体”的新结构解决了这个问题。新开发的'Cal.35SQ'型尺寸*晶体单元的直径为4.3mm×长度为18.5mm(图3)。此外,精工苏瓦株式会社还能够调整水晶单元的内部结构,以便克服腕表连接在佩戴者手腕上时经常受到的振动和撞击所引起的问题。
It is Seiko Suva Co., on the shores of Lake Suva, and it is quietly controlling this growing competitor. One of the factors that led Seiko Suva to lead its competitors was the company's success in making crystal units more compact. The traditional crystal device is very large in size and cannot be loaded into a watch-like thing (Fig. 2). Seiko Suva solved this problem by adopting a new structure called "tuning fork crystal". The newly developed 'Cal.35SQ' size* crystal unit has a diameter of 4.3 mm and a length of 18.5 mm (Fig. 3). In addition, Seiko Suva can adjust the internal structure of the crystal unit to overcome the problems caused by vibrations and impacts that are often encountered when the watch is attached to the wearer's wrist.
*此时公司开发的音叉式水晶单元用于Suwa Seikosha内部制造的手表。因此,“我们没有给他们一个特定的产品型号,只是通过他们的机芯名称或手表的操作机制(Calibre,或'Cal。')来提及它们,”Mutsumi Negita说。
* At this time, the company's tuning fork crystal unit was used for watches made inside Suwa Seikosha. Therefore, "we didn't give them a specific product model, just mention them by their movement name or the operating mechanism of the watch (Calibre, or 'Cal.')," Mutsumi Negita said.
图3:Quartz Astron中使用的音叉晶体单元
采用新开发的音叉结构,使Suwa Seikosha能够成功制造出更小的晶体单元,半径仅为4.3mm,长度为18.5mm。它被分配了型号“Type Cal.35SQ”并且具有8.192kHz的正常频率。Figure 3: Tuning fork crystal unit used in Quartz Astron
With the newly developed tuning fork structure, Suwa Seikosha was able to successfully manufacture smaller crystal units with a radius of only 4.3 mm and a length of 18.5 mm. It is assigned the model "Type Cal.35SQ" and has a normal frequency of 8.192 kHz.- 阅读(178)
- [行业新闻]爱普生晶振新推出差分输出晶体振荡器2018年08月25日 10:35
日本精工爱普生晶振公司成立于1942年5月,迄今为止已经成了晶振行业较出名的进口晶振品牌,日本爱普生晶振,KDS大真空晶振,SEIKO精工晶振,KYOCERA晶振,NDK晶振均是日系较大晶振品牌供应商.市场竞争力比较大,各大进口晶振品牌制造商也不断的研发生产新产品.
Japan Seiko Epson Crystal Co., Ltd. was established in May 1942. So far, it has become a well-known imported crystal brand in the crystal industry. Japan Epson crystal oscillator, KDS large vacuum crystal oscillator,Seiko crystaloscillator, KYOCERA crystal oscillator, NDK crystal oscillator are Japanese large crystal oscillators. Brand suppliers. The market competitiveness is relatively large, and the major imported crystal brand manufacturers are constantly developing and producing new products.
就在2014年3月26日,爱普生晶振公司推出SG7050EBN晶振.这款石英晶体振荡器型号是下一代的差分输出晶振(差分信号手于高频时钟和数据信号,以实现良好的信号完整性和高抗噪性.如:高精度,高温度,低抖动,低功耗).可实现极低的相位抖动(时钟周期之前的波动,这可能导致数据传输期间的们错误).
On March 26, 2014, Epson Crystal Corporation introduced the SG7050EBN crystal. This quartz crystal oscillator model is the next generation of differential output crystal (differential signal hands on high frequency clock and data signals for good signal integrity and High noise immunity. For example: high precision, high temperature, low jitter, low power consumption. It can achieve extremely low phase jitter (fluctuations before the clock cycle, which may cause errors during data transmission).
SG7050EBN晶振的频率范围在100~175MHZ之间,可以实现65fs的相位抖动.些性能适用于数据中心和中心局使用的1040和100千兆位以太网互连.SG7050EBN晶振将用于有线网络设备使用,包括运营商和企业,如高端路由器和交换机.
The SG7050EBN crystal has a frequency range of 100 to 175 MHz and can achieve phase jitter of 65 fs. These features are suitable for 1040 and 100 Gigabit Ethernet interconnections used in data centers and central offices. The SG7050EBN crystal oscillator will be used for wired network equipment. , including operators and enterprises, such as high-end routers and switches.
SG7050EBN采用专为低噪声设计的振荡器IC和采用爱普生专用QMEMS(QMEMS结合了”石英”,一种具有出色稳定性和精度的压电晶体材料,以采用微制造技术设计的”MEMS”微机系统.结合了MEMS技术的优势和石英材料的基本优势.也是精工爱普生晶振公司注册的商标)工艺制造的高频基波(HFF)AT切晶体(HFF晶体单元是通过光刻工艺蚀刻成倒置台面形状并以高基频振荡的晶体芯片).实现65fs相位抖动.爱普生的HFF晶体技术比传统的三次谐波晶体更加可靠.爱普生晶振公司后续也打算通过逐步发布支持HCSL和LVDS输出标准的新产品来解决网络设备中使用的各种差分输出格式.EPSON晶振致力于提高客户的设计自由度,采用高度紧凑的5032(5.0*3.2*1.0mm)封装.
The SG7050EBN uses an oscillator IC designed for low noise and a QMEMS (QMEMS combined with quartz), a piezoelectric crystal material with excellent stability and precision, and a "MEMS" microcomputer system designed with micro-fabrication technology. Combines the advantages of MEMS technology with the basic advantages of quartz materials. It is also a trademark of Seiko Epson Crystal Co., Ltd.) Processed high-frequency fundamental (HFF) AT-cut crystal (HFF crystal unit is etched into an inverted mesa shape by photolithography and High-frequency oscillation crystal chip). Realize 65fs phase jitter. Epson's HFF crystal technology is more reliable than traditional third-harmonic crystal. Epson Crystal's follow-up is also intended to solve network equipment by gradually releasing new products supporting HCSL and LVDS standards. Various differential output formats used in the EPSON crystal oscillator are dedicated to improving the customer's design freedom in a highly compact 5032 (5.0*3.2*1.0mm) package.
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- [行业新闻]爱普生新推可编程晶体振荡器SG-8101CE晶振及SG-9101CG晶振2018年08月20日 09:37
精工爱普生晶振公司将推广备受欢迎的可编程晶体振荡器系列,推出两个新开发的差分晶振系列产品。与同类产品相比,新型SG-8101晶振系列和SG-9101晶振系列具有更宽的工作温度范围和50%的电流消耗,而SG-8101晶振的频率容差更高66%。用户可以使用SG-Writer II* 1编程工具对SG-8101系列和扩频振荡器进行编程,从而降低SG-9101系列中的光谱EMI辐射。量产计划于2016年6月开始。
Seiko Epson Crystal will introduce the popular family of programmable crystal oscillators and introduce two newly developed differential crystal oscillators. Compared to similar products, the new SG-8101 crystal series and the SG-9101 crystal series have a wider operating temperature range and 50% current consumption, while the SG-8101 crystal has a 66% higher frequency tolerance. Users can program the SG-8101 Series and Spread Spectrum Oscillator with the SG-Writer II* 1 programming tool to reduce spectral EMI emissions in the SG-9101 Series. The mass production plan begins in June 2016.
近年来,越来越需要能够在多种环境中使用的多功率及多功能小型电子设备。包括极端户外和工厂安装,对具有出色频率稳定性和耐受各种温度的能力的晶体振荡器的需求已经增加。 。
In recent years, there has been an increasing demand for multi-power and multi-function small electronic devices that can be used in a variety of environments. Including extreme outdoor and factory installations, the demand for crystal oscillators with excellent frequency stability and ability to withstand various temperatures has increased. .
自从1997年推出世界上第一台可编程晶振SG-8000系列以来,爱普生晶振公司为市场提供了小巧,精确的可编程振荡器。爱普生开发了新的SG-8101系列,配备了高效,紧凑和精密技术的仓库。和SG-9101系列结合使用QMEMS * 2,半导体和温度补偿晶体振荡器(TCXO)频率调节技术。
Since the introduction of the world's first programmable crystal oscillator SG-8000 series in 1997, Epson Crystal has provided the market with a compact, accurate programmable oscillator. Epson has developed the new SG-8101 series, equipped with efficient, compact and sophisticated technology warehouses. Combined with the SG-9101 series, QMEMS* 2, semiconductor and temperature compensated crystal oscillator (TCXO) frequency adjustment technology.
虽然这两个系列都提供了与早期爱普生产品相当的频率和其他参数的简单可编程性(SG-8101晶振为,SG-9001晶振为SG-9101晶振),它们还具有更宽的工作温度范围,最高限制为105℃。除了2.5 mm x 2.0 mm封装,使电子制造商能够节省电路板空间外,石英晶体振荡器还将提供以下常用封装尺寸:3.2 mm x 2.5 mm,5.0 mm x 3.2 mm和7.0 mm x 5.0毫米。
Although both series offer simple programmability with frequency and other parameters comparable to earlier Epson products (SG-8101 crystal, SG-9001 crystal is SG-9101 crystal), they also have a wider operating temperature range The maximum limit is 105 °C. In addition to the 2.5 mm x 2.0 mm package, electronics manufacturers can save board space, and the oscillators are available in the following common package sizes: 3.2 mm x 2.5 mm, 5.0 mm x 3.2 mm, and 7.0 mm x 5.0 mm.
与同类产品相比,SG-8101系列振荡器的频率容差约为66%,电流消耗降低50%。使用扩频的SG-9101系列振荡器比可比数据消耗的电流低75%。用户可以使用Epson SG-Writer II(另售)将产品编程到所需的输出频率,以及所需的输出频率调制曲线和周期。
Compared with similar products, the SG-8101 series oscillators have a frequency tolerance of approximately 66% and a current consumption reduction of 50%. The spread-spectrum SG-9101 series oscillator consumes 75% less current than comparable data. Users can use the Epson SG-Writer II (sold separately) to program the product to the desired output frequency, as well as the desired output frequency modulation curve and period.
这些振荡器可在各种环境条件下使用。它们还将显着提高性能,降低功耗要求,快速开发周期和小批量生产。
These oscillators can be used in a variety of environmental conditions. They will also significantly improve performance, reduce power requirements, rapid development cycles and small batch production.
* 1 SG-Writer II和可选组件将通过软件更新(免费)支持SG-8002和SG-8003系列中的现有产品以及新SG-8101和SG-9101系列中的产品。
* 2 QMEMS:
QMEMS结合了“石英”,一种具有优异频率稳定性和高精度的优异特性的晶体材料,以及“MEMS”(微机电系统)。
QMEMS器件通过微晶加工工艺在晶体材料上而不是像MEMS这样的半导体材料上生产,在紧凑的封装中提供高性能。QMEMS是Seiko Epson Corporation的注册商标。
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- [公司新闻]爱普生晶振系列晶体振荡器2018年08月02日 14:45
在过去的几年中,娱乐,游戏和便携式市场的电子设备加速的增长推动了石英晶体和晶体振荡器的需求不断增加,甚至达到了前所未有的生产水平以及生产技术.早在十几年前,爱普生晶振的销量以及生产技术还跟不上市场的需求.比如2012晶振会无法正常出货,体积较小,生产达不到技术要求.但是随着这几年的市场需求量的增长,爱普生晶振也在不断的提升生产技术,不断的改进不足,从而使得更小尺寸1612封装晶振可以正常批量出货.
一直以来石英晶体振荡器的高Q值和稳定的温度特性,使得其在消费,商业,工业以及军事产品中起到重要的作用.自2000年至2001年”互联网”市场崩溃以来,对石英晶体以及振荡器的需求每年稳定增长4%至10%.
在早些时候,典型的GSM手机有四组不同的压电频率控制和发电组件:RF SAW滤波器(使用压电钽酸锂或铌酸锂的900 MHz至2 GHz)用于在天线和收发器芯片组之间进行传输和接收滤波;如果使用超外差降频转换,则使用SAW滤波器(主要使用石英为50至400 MHz); TCXO(13/26 MHz,使用石英晶体)作为收发器合成器中的时钟参考,用于信道化;和音叉(使用石英晶体的32.768 kHz)用于基带部分的待机时钟.
后来,直接转换技术的成功开发在许多GSM手机中废弃了IF SAW滤波器.几年前,带有片上数字补偿晶体振荡器(DCXO)电路的GSM收发器芯片组消除了对TCXO晶振的需求.但是,仍然需要片外石英晶体.
现在的手持设备似乎没有变小,实际上它们已经变得非常小了,但是手机虽小,功能却大的多.以适应消费者多频段,多模,DSC,DVC,MP3,GPS,互联网接入,蓝牙,DTV等所需的更多功能.跟之前想法相反,随着时间的推移,需要越来越少的片外石英晶体,晶体振荡器和SAW元件,现在手机中存在着更多的石英晶体,音叉晶振,晶体振荡器,高精度温补晶振等.虽然这些组件的独特制造和封装要求使它们几乎不可能集成到成熟的硅IC平台上.
在有线和无线市场的蓬勃发展,从而使得石英晶体以及其高频SAW声表面滤波器得到广泛应用.
传统的石英晶振尺寸型号以4.1*1.5,3.2*1.5以及2.0*1.2mm提供.现在也是将这种石英音叉的厚度达到0.4毫米或者更低,从而适用于薄型产品的使用.小于5032封装石英晶振通常需要在真空中密封从而维持阻抗完整性.低兆赫兹小尺寸石英晶振的坏料也需要倾斜于石英晶体边缘,其变薄.从而有效的获得能量.在未来的几年内将出现更小尺寸的石英晶体(1.6*1.0以及1.0*0.8mm)晶振的使用.全球石英晶体供应商正在为这些小尺寸晶振工作.
很多人都不知道相当多的石英产品(石英晶体,石英音叉晶体,石英陀螺传感器等)正在制造一些MEMS(微机电系统)处理.如光刻,金属化,蚀刻,牺牲层沉积去除,金蚀刻保护等.实际上,复杂的加工步骤非平面金属化方案.由于石英晶体的硬度而耐蚀刻,高度各向异性的石英晶体的不同蚀刻速率等,使得小型化的石英晶体产品的加工更加技术上与许多基于硅的MEMS工艺相比具有挑战性.Epson Toyocom几年前创造了“QMEMS”这一术语,以认识到将石英和MEMS技术与下一代石英晶体器件联系起来的重要性.
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- [行业新闻]Transko crystal特兰斯科温补晶振选型列表2018年07月21日 09:49
- 特兰斯科晶振公司总部位于美国加利福尼亚州。公司自1992年成立以来一直致力于研发生产高精密TCXO温补晶振.从1993年开始在美国加利福尼亚州拉古纳山开设制造工厂,引进高端生产设备,在历经四年的时间后开始正式生产TCXO温补晶振以及VCXO压控晶振.在这一年,Transko特兰斯科晶振公司取得了非常大的增长突破。
图片 零件号 符合RoHS 封装 逻辑(输出) 供电电压 频率 TX-O
合规 2.5 X 2.0陶瓷
4焊盘SMD截断正弦波 2.5V,2.8V,3.0V,3.3V
16.000MHz~26.000MHz TX-U
合规 2.0 X 1.6陶瓷
4垫SMD截断正弦波 1.8V,2.5V
2.8V,3.0V,3.3V13.000MHz~52.000MHz TX-N
合规 2.5 X 2.0陶瓷
4焊盘SMD截断正弦波 1.8V,2.5V,2.8V 13.000MHz~52.000MHz TX-L
合规 3.2 X 2.5陶瓷
4垫SMDCMOS
削波正弦波1.8V,2.5V
2.8V,3.0V,3.3V4.000MHz~54.000MHz TX-M
合规 3.2 X 2.5陶瓷
4焊盘SMD
(模拟补偿)截断正弦波 1.8V,2.5V
2.8V,3.0V,3.3V16.000MHz~26.000MHz TX-Q
合规 3.2 X 2.5陶瓷
4垫SMDCMOS 1.8V,2.5V
2.8V,3.0V,3.3V4.000MHz~54.000MHz TFC5
合规 5.0 X 3.2陶瓷
4垫SMDCMOS
削波正弦波3.3V,5.0V 10.000MHz~40.000MHz TX-J
合规 5.0 X 3.2陶瓷
4垫SMDCMOS
削波正弦波3.3V,5.0V 10.000MHz~40.000MHz TE-J
合规 5.0 X 3.2 Epoxy
4 Pad SMDCMOS
削波正弦波1.8V,2.5V,3.3V 13.000MHz~52.000MHz TX-T
合规 5.0 X 3.2陶瓷
4垫SMDCMOS
削波正弦波1.8V,2.5V,2.8V
3.0V,3.3V,5.0V4.000MHz~54.000MHz TFC
合规 7.0 X 5.0陶瓷
SMDCMOS
削波正弦波3.3V,5.0V 5.000MHz~40.000MHz TE-S
合规 7.0 X 5.0 Epoxy
4 Pad SMDCMOS
削波正弦波1.8V,2.5V,3.3V 10.000MHz~40.000MHz 2px;="" text-align:="" -webkit-center;="" "="">2px;="" text-align:="" -webkit-center;="" "=""> TXCS
合规 7.0 X 5.0陶瓷
SMDLVCMOS
截断正弦波3.3V 10.000MHz~16.376MHz TX-K
合规 7.0 X 5.0陶瓷
4垫SMDCMOS
削波正弦波2.5V,3.3V 5.000MHz~52.000MHz 2px;text-align:-webkit-center"=""> TX-P
合规 7.0 X 5.0陶瓷
4垫SMDCMOS
削波正弦波3.3V,5.0V 5.000MHz~40.000MHz TX-S
合规 7.0 X 5.0陶瓷
SMDCMOS
削波正弦波3.3V,5.0V 5.000MHz~50.000MHz TX-SB
合规 7.0 X 5.0陶瓷
SMD截断正弦波 3.3V,5.0V 10.000MHz~27.000MHz TX-R
合规 7.0 X 5.0陶瓷
4垫SMDCMOS 3.3V,5.0V 1.250MHz~156.250MHz 2px;="" text-align:="" -webkit-center;="" "="">2px;="" text-align:="" -webkit-center;="" "=""> TX-V
合规 7.0 X 5.0陶瓷
SMDCMOS
削波正弦波3.3V,5.0V 5.000MHz~40.000MHz TX-A
合规 14针DIP通孔
4.5mm高度CMOS / TTL
CSW / SW3.3V,5.0V 1kHz~800.000MHz 2px;text-align:-webkit-center"=""> TX-AL
合规 14针DIP通孔
4.5mm高度LVDS
LVPECL3.3V,5.0V 750kHz~800.000MHz TX-B
合规 14针DIP通孔
8.5mm高度CMOS / TTL
CSW / SW3.3V,5.0V 1kHz~800.000MHz 2px;text-align:-webkit-center"=""> TX-BL
合规 14针DIP通孔
8.5mm高度LVDS
LVPECL3.3V,5.0V 750kHz~800.000MHz TX-C
合规 20.0 X 20.0
DIP通孔CMOS / TTL
CSW / SW3.3V,5.0V 1kHz~800.000MHz TX-d
合规 14.3 X 8.7 FR4 PCB
4焊盘SMDCMOS / TTL
CSW / SW3.3V,5.0V 1kHz~800.000MHz TX-D6
合规 14.3 X 8.7 FR4 PCB
6焊盘SMDCMOS / TTL
LVDS / LVPECL
CSW / SW3.3V,5.0V 1kHz~800.000MHz TX-E
合规 18.3 X 11.7 PCB SMD CMOS / TTL
CSW / SW3.3V,5.0V 1kHz~800.000MHz 2px;text-align:-webkit-center"=""> TX-EL
合规 18.3 X 11.7 PCB SMD LVDS
LVPECL3.3V,5.0V 750kHz~800.000MHz TX-F4
合规 11.4 X 9.8 PCB
4焊盘SMDCMOS / TTL
CSW / SW3.3V,5.0V 1kHz~800.000MHz TX-F6
合规 11.4 X 9.8 PCB
6焊盘SMDCMOS / TTL
CSW / SW3.3V,5.0V 1kHz~800.000MHz VTXLN
合规 11.4 X 9.6 PCB
4焊盘SMD
-150dBC / Hz @ 1kHzHCMOS 3.3V,5.0V 10.000MHz~20.000MHz TX-G
合规 11.4 X 11.6 PCB
鸥翼式SMDCMOS / TTL
CSW / SW3.3V,5.0V 1.250MHz~50.000MHz TX-H
合规 14针DIP
密封
通孔CMOS / TTL
CSW / SW3.3V,5.0V 1kHz~800.000MHz 2px;text-align:-webkit-center"=""> TFL
合规 14针DIP
密封
通孔LVDS
LVPECL3.3V,5.0V 750kHz~800.000MHz THH
合规 8针DIP
密封
通孔CMOS / TTL
CSW / SW3.3V,5.0V 1kHz~800.000MHz 2px;text-align:-webkit-center"=""> THL
合规 8针DIP
密封
通孔LVDS
LVPECL3.3V,5.0V 750kHz~800.000MHz The company is Transko crystal in California, USA. Since its establishment in 1992, the company has been committed to the development and production of high-precision TCXO temperature-compensated crystal oscillators. Since 1993, it has opened a manufacturing plant in Laguna Hills, California, USA, and introduced high-end production equipment. After four years, it began to officially produce TCXO. Temperature-compensated crystal oscillators and VCXO voltage-controlled crystal oscillators. In this year, Transko Tranco Crystal has achieved a very large growth breakthrough.
- 阅读(334)
- [公司新闻]Frequency晶振空间应用晶体型号2018年06月05日 10:42
Fre-techCrystal晶振公司利用其高精密的设计和制造能力成为全球领先的晶体控制振荡器,晶体振荡器和声表面滤波器的供应商,为那些为全球太空行业提供原始设备制造商提供服务。典型的应用包括深空探测,商业和国防卫星和地面基地ICBM筒仓。此外,Fre-tech是高精密和空间级频率控制产品的全球领先供应商,其历史可追溯至1961年的军事和航天计划。Fre-tech的Hi-Rel制造工厂为世界领先的商业和军事生产商卫星通过其经验丰富的员工和世界一流的制造工厂。
2px"="" style="color:#222222">Fre-tech uses its precision design and manufacturing capabilities to be the world's leading supplier of crystal controlled oscillators, crystal units and SAW filters to those OEM's servicing the world wide space industries. Typical applications include Deep Space Exploration, Commercial & Defense Satellites and Ground Base ICBM Silos. In addition, Fre-tech is the world's leading supplier of precision and space grade frequency control products, with heritage on both military and space programs dating back to 1961. Fre-tech's Hi–Rel manufacturing facility supplies the worlds leading producers of commercial and military satellites through its experienced staff and world class manufacturing plant.
2px"="" style="color:#222222">
2px"="" style="color:#222222">
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