Crystal Oscillator PPM Error Analysis and Calculation Method
Crystal oscillator accuracy index: PPM
Crystal oscillator accuracy is usually measured in PPM (Parts Per Million), which describes the frequency stability or deviation of the crystal oscillator. PPM represents the relative error between the actual output frequency and the nominal frequency, and is an important parameter for measuring the frequency accuracy of the crystal oscillator.
How to calculate the frequency difference of the crystal oscillator
The frequency difference reflects the difference between the actual frequency and the nominal frequency of the crystal oscillator. The PPM value of the frequency difference is calculated by the formula as follows:
PPM= (actual frequency − nominal frequency) / nominal frequency X 106
Explanation:
Actual frequency: The actual operating frequency of the crystal oscillator measured by a frequency meter or other appropriate instrument.
Nominal frequency: The standard or nominal frequency specified by the crystal oscillator manufacturer in the crystal oscillator specification book.
Example:
For example, if the nominal frequency of a crystal oscillator is 32.768 kHz and the actual measured frequency is 32.7685 kHz, then the PPM is calculated as follows:
PPM=(32768.5Hz−32768Hz)/32768Hz*106≈15.26
Frequency difference type: normal temperature frequency difference V.S. temperature frequency difference
(curve graph)
The frequency stability of a crystal oscillator will change under different temperature conditions. For a crystal oscillator, its frequency accuracy generally includes two important indicators: normal temperature frequency difference and temperature frequency difference:
1. Normal temperature frequency difference (Frequency Tolerance): It is also called frequency deviation in the YXC specification (see the figure below). It is the deviation from the nominal frequency at normal temperature (25°C), usually expressed in parts per million (PPM).
2. Frequency Versus Temperature Characteristics: It is also called frequency-temperature characteristics in the YXC specification (see the figure below), which refers to the maximum deviation of the actual frequency relative to the nominal frequency within the set operating temperature range, also expressed in parts per million (PPM).
RTC crystal oscillator 32.768KHz frequency accuracy PPM value and time deviation calculation
For the 32.768kHz RTC clock crystal oscillator, the daily time error range can be derived from its frequency accuracy (PPM). The specific steps are as follows:
For example: If the crystal oscillator 32.768KHz accuracy is ±10PPM, the calculation formula for the time error of one day is as follows:
10(PPM)×24(1 day=24 hours)×60(1 hour=60 minutes)×60(1 minute=60 seconds)=864000*1/1000000=0.864 seconds
That is: the time error of the RTC crystal oscillator does not exceed 0.864 seconds per day, that is: if it is +10PPM, it is at most 0.864 seconds faster per day, if it is -10PPM, it is at most 0.864 seconds slower per day.
(Typical application circuit of 32.768KHz crystal resonator)
RTC clock crystal oscillator 32.768kHz daily time error reference table:
a)±10PPM: The actual frequency range is 32768.32768Hz~32767.67232Hz, the daily time error is 0.864×1=0.864 seconds, the monthly error is 25.92 seconds, and the total deviation in one year is 5.184 minutes.
b)±20PPM: The actual frequency range is 32768.65536Hz~32767.34464Hz, the daily time error is 0.864×2=1.728 seconds, the monthly error is 51.84 seconds, and the total deviation in one year is 10.368 minutes.
c)±30PPM: The actual frequency range is 32768.98304Hz~32767.01696Hz, the daily time error is 0.864×3=2.592 seconds, the monthly error is 77.76 seconds, and the total deviation in one year is 15.552 minutes.
- |
- +1 赞 0
- 收藏
- 评论 0
本文由玄子转载自YXC Official Website,原文标题为:Crystal Oscillator PPM Error Analysis and Calculation Method,本站所有转载文章系出于传递更多信息之目的,且明确注明来源,不希望被转载的媒体或个人可与我们联系,我们将立即进行删除处理。
相关推荐
Tips for Crystal Oscillator Circuit Design, Essential Skills for Engineers!
As an indispensable signal transmitter in the clock circuit, the crystal oscillator is required for the microcontroller to operate normally. Therefore, the participation of the crystal oscillator is also indispensable in the design of electronic circuits. A good crystal oscillator circuit design can provide the best space utilization for electronics and play the greatest functional role.
技术探讨 发布时间 : 2024-11-19
Does a Passive Crystal Oscillator Have a Direction?
A passive crystal oscillator has no direction, and the pins of a passive crystal oscillator do not distinguish between positive and negative poles.
技术探讨 发布时间 : 2024-11-13
What Does 30pf Mean for a Crystal Oscillator?
30PF for a crystal oscillator refers to an external capacitor of 30PF. The choice of capacitance can directly affect the start-up time, output frequency accuracy and frequency stability of a passive crystal oscillator.
技术探讨 发布时间 : 2024-10-26
扬兴晶振(YXC)晶振选型指南
目录- 公司简介 石英晶体介绍 直插金属表面石英晶体谐振器 贴片金属表面石英晶体谐振器 32.768KHZ贴片金属表面石英晶体谐振器 车规级贴片金属表面石英晶体谐振器 贴片陶瓷表面石英晶体谐振器 贴片金属表面振荡器 贴片金属表面可编程振荡器
型号- YSX1612SL,YSO140TC,YSX211SL,YSO130HR,HC-49XSMD,YSX1610SK,YSX1612SC,YSX2012SK,YSX211SC,YSO230LR,YSV310PR-VCXO,YSO120TK,YT-38,HC-49US,YST310S,YSX306GA,YSO210PR,YSO690PR,HC-49SMD,YSX146GA,YSV220PR-VCXO,YSX1210SL,YSX321SL,YSX221SC,YSX320GA,YSX531SL,YSX530GA,YSX321SC,YT-26,YSX221SL,YSX531SC,YSX530SC,YSO110TR
YSO251PJ OM2EIBXFM-250M SMD-3225-250MHZ-3.3V- ±2.5PPM QUARTZ CRYSTAL OSCILLATOR SPECIFICATION
型号- OM2EIBXFM-250M,YSO251PJ,YSO251PJ 250.00000 MHZ 3.3V ± 2.5PPM
YSO210PR OA1EIB112-148.5M 石英晶体振荡器 产品规格书
型号- OA1EIB112-148.5M,YSO210PR 148.50000MHZ 3.3V -/+20PPM,YSO210PR
YXC automotive grade resonator 8MHz, Passive Crystal Oscillator 3225 Package for Car Bluetooth Module
Bluetooth module is a PCBA board with integrated Bluetooth function, which is used for short-distance wireless communication. It is divided into Bluetooth data module and Bluetooth voice module according to its function. Bluetooth module refers to a collection of basic circuits of chips with integrated Bluetooth function, which is used for wireless network communication.
产品 发布时间 : 2024-06-23
YXC Programmable Differential Crystal Oscillator YSO210PR Series, Frequency 155.52MHz, LVPECL Output, Used in Switches
A switch is a network device that is mainly used for forwarding electrical (optical) signals, allowing independent communication between any two network nodes connected to the switch.Switches are not limited to Ethernet applications, but also come in many forms such as telephone voice switches and fiber optic switches to meet different network needs.Switches require a stable clock signal to synchronize the transmission and processing of network data.
应用方案 发布时间 : 2024-06-22
YSO110TR OT2JI-111-12.288M 石英晶体振荡器 产品规格书
型号- YSO110TR 12.288MHZ 1.8V-3.3V -/+10PPM,OT2JI-111-12.288M,YSO110TR
YXC 16MHz Automotive-grade Resonator YSX321SC, 3225-4P Package, Operating Temperature -40~125℃, Used in Vehicle HUD
the HUD system displays relevant driving information, such as vehicle speed, navigation instructions, warnings, etc., directly on a transparent display panel in front of the driver‘s field of vision by mapping images or information. The clock signal of the crystal oscillator is used to control image generation and update, ensuring that the image is updated within a sustained time interval and maintaining the real-time and continuity of information.
应用方案 发布时间 : 2024-05-16
电子商城
品牌:EPSON
品类:Temperature Compensated Crystal Oscillator
价格:¥3.4249
现货: 57,046
现货市场
服务
测试范围:扬兴晶振全系列晶体,通过对晶体回路匹配分析,调整频率、驱动功率和起振能力,解决频偏、不起振、干扰、频率错误等问题。技术专家免费分析,测完如有问题,会进一步晶振烧录/修改电路。
实验室地址: 深圳 提交需求>
登录 | 立即注册
提交评论