PIC18F14K50与电磁兼容遵循什么一般规则

描述一下环境，我们就能更好地提出建议。例如，你是更担心***扰还是成为造成干扰的人？你更关心传导还是辐射干扰？



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    Describe the environment and we will be able to better make recommendations.
 
For example are you more worried about being interfered with or being the one causing interference?
 
Are you more concerned with conducted or radiated interference? 

我想不出任何原因，每个IO都需要一个上限和很多原因，这可能是坏的。唯一我能想到的另一个引脚需要一个上限是VUSB引脚。见DS第8章。也可以看到22.6个“USB电源模式”。



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    I can't think of any reason each IO would need a cap and a lot of reasons it could be bad.  
The only other pin I can think of that needs a cap is the Vu*** pin.  See DS chapter 8.0.  See also 22.6 "USB Power Modes".
 
HTH

如此危险的话……如果你能准确地引用你读到的内容，或者链接到你读到的地方，就会有所帮助。最有可能的是，它指的是输出管脚在PIC安装板上的外面发送信号。如果你对高频d不熟练，那么分析RF发射是一门黑艺术。设计。



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Such dangerous words...
It would help if you could quote exactly what you read, or link to where you read it.
Most likely, it was talking about output pins sending signals outside the board the PIC is mounted on.
Analysing RF emissions is a bit of a black art if you are not skilled in high frequency design.
 

通常你会看到RC作为输入的低通滤波器来限制到达引脚的噪声。通常我用一个10K系列的输入引脚，在引脚的10NF帽。这给出了1.6KHz。添加一个ESD二极管，例如OnsemiMMQA5V6T，以限制电感性负载切换的有效性，避免引起问题。滤波是件好事（磁性和ESD二极管），但保持电感在3pF以下，以防止480Mhz信号中断。如果您有任何问题，请张贴您的示意图和环境。小事：一个EMI案例使我困惑了好几个月，因为以太网节点一直关闭。直到它被发现是徽章阅读器的一部分，墙的另一侧是工业用8000公斤（15000磅）电梯的电梯控制系统的一部分，它才变得毫无意义。电梯制造商有大量关于EMI以及如何控制EMI的文献，但是墙的另一边的个人在安装徽章阅读器时忽略了所有这些。简单的解决办法是把徽章阅读器2M（6英尺）移到墙下，它总是工作得很好！是的，我仍然对一个只有10PF负载的滤波器电路进行了笑。问题是10PF负载是由于范围探测器。所以只要我在信号范围内，一切都有效！在电磁场处理过程中，有很多理由可以看到一个简单而不简单的过滤器。我仍然喜欢Henry Ott的任何一本书和文章。我只做了四十年，所以我还有很多东西要学。



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    Often you do see RC as a low pass filter on inputs to limit noise reaching the pin. Often I used a 10K in series to the Input pin, with a 10nF cap at the pin. This gives a 1.6KHz.
 
Add an ESD Diode, such as the Onsemi MMQA5V6T, to limit the effective of inductive load switching from causing issues. 
 
With USB2.0 always watch out for any capacitive loading on D+ and D-.  Filtering is a good thing (magnetics and ESD diodes) but keep the inductance below 3pF to prevent killing the 480Mhz signal. 
 
If you have any questions, post up your schematic and what the environment went into.
 
Trivia: one case of EMI had me baffled for months as an Ethernet node kept shutting down.  Nothing made sense until it was discovered it was part of a badge reader, and the other side of a wall was part of an elevator control system for an industrial 8 000 kg (15,000 pound) lift.  The lift manufacturer had a ton of literature about EMI and how to control it, but the personal on the other side of the wall ignored all that when installing a badge reader.  Simple solution was to move the badge reader 2m (6 ft) further down the wall, weere it always worked fine!
 
Yes I still laugh about a filter circuit I built that only worked with a 10pF load. The problem was the 10pF load was due to a scope probe. So as long I scoped the signal, everything worked!
 
Lots of reasons to see simple, and not so simple, filters on a board when dealing with electromagnetic fields.  I still enjoy any of Henry Ott's books and articles.  I've only been at this for forty years, so I still have lots to learn.

下面的16:00的视频说我需要电容器，但是我没有射频输入信号。我只有两个开关和3个模拟引脚，我用ADC。所以我不需要在我的情况他们？HTTPS://www. Youtub.com /手表？V= DA2TZNC3LIG



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    The following video at 16:00 says I need capacitors but I don't have RF input signals.I only have two switches and 3 analog pins that I use ADC.So I don't need them in my case?
 
https://www.youtube.com/watch?v=dA2TzNC3Lig

对ADC的输入进行低通滤波总是很好的做法。但是要仔细考虑以免在读数中引起误差（由于输入电阻等）。通常用简单的RC滤波器来跳动开关也是一个好主意。



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It's always good practice to low-pass filter the input to ADC's. However it can take carefull thought so as not to induce errors in the readings (due to input resistance etc.).
It's also usually a good idea to de-bounce switches with a simple RC filter.

***



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    ****

这里是示意图。JP6用于蓝牙Bootloader和JP4，用于蓝牙通信。



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So here is the schematic.JP6 is used for u*** bootloader and JP4 for bluetooth communication.
 

您的图像包含一个链接：https://.-1.dropbox.com/t/2/AACxFwyCHhC4w020j3SV89pSH3IqBw1tnJNO7TjBYduzg/12/49097982/png/32x32/1/2/schematic.PNG/EJ6c2yUY2IQCIAcoBw/kjedyUY9iNaSH9aCwFuyQg6O1KVmGtp51ZrY？大小= 2048 X1536和；



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    Your image contains a link to:
https://photos-1.dropbox.com/t/2/AACxFwyCHhC4w020j3SV89pSH3IqBw1tnJNO7TjBYyduzg/12/49097982/png/32x32/1/_/1/2/schematic.PNG/EJ6c2yUY2IQCIAcoBw/kjedyUOxPI9iNaSH9aCwfuryQgq6O1KVmGtpN51ZZrY?size=2048x1536&size_mode=3
browsing to there just says:

我更新了它。



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    I updated it.