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毛玲燕

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dsPIC原理图设计加载代码时通知“无效ID”

我的DSPIC33 EP64 MC202遇到了一些问题。我认为这是一个硬件问题，但我还不确定。我设计了硬件，设计了固件，调试模式下一切都很好。因此，我在调试模式下停止使用它，并且我确实编程了它。一个月后，它没有理由停止，所以我试图调试它，但是当我试图加载代码时，出现了一条消息，通知“无效ID”。我试过一切，很好，这意味着DSPIC死了，对吗？所以我把另一个DSPIC，同一个模型，它工作得很好，但是，最近的一个，同样的事情发生了，它停止了，当我试图调试，消息出现：“目标设备ID（0x1D39万）是一个无效的设备ID”WHELL，我将把我的示意图和规范放在数据表中。T。我可以看到VCAP中的连接不是推荐的，但是，如果我不把VCAP放在VDD中，调试不起作用。我能做什么？这会是DSPIC失败的原因吗？我的示意图和推荐的设计附图是在SigaTrdDSPICI的名义下的，这是因为电源的缘故，我用LM317转换为138V到3.3V。这个设备需要24H的功能，这个电源是一个好的选择吗？我的设计的源代码是以PoNTE3.3V的名字附在这个帖子上的。任何帮助都是很棒的。以我最好的回报。丹尼尔。

以上来自于百度翻译


      以下为原文

    I'm having some problems with my dsPIC33EP64MC202. I believe it is a hardware problem, but I'm not sure yet.
I designed the hardware, designed the firmware, and everything was fine in debug mode. So, I stopped to use it in debug mode and I programmed it definitely. One month later it stopped with no reason, so I tried to debug it, but when I tried to load the code the a message appears to inform "Invalid ID" . I tried everything and well, it means the dsPIC died, am I right ? So I put another dsPIC, same model and it worked fine, but, aproximately one mounth later, the same thing happened, it stopped and when I tried to debug, the message appears: "Target Device ID (0x1d390000) is an Invalid Device ID"
Whell, I will put here my schematic and the specification in datasheet . I can see that the connection in vcap is not the recommended, but, if I do not put vcap in VDD, debug does not work. What can I do ? Would it be the responsible for the dsPIC fail ? The figure with my schematic and the recommended design is attached to this post under the name schematicDSPIC

I'm thinking it woul be because of the soure power, I use a LM317 to convert 13.8V to 3.3V. The device need to be functioning 24hs, is this source power a good choice ? The figure with my design of the source is attached to this post under the name fonte3.3V.

Any help would be great.
With my best regrads.
Daniel.
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回帖（7）

周润艺

2018-9-18 14:57:54
LM317电路的原理图是否正确？你是如何计算出这个电路的输出电压为3.3伏？你测量过LM317电路的输出电压了吗？还有，你在哪里得到一个375欧姆电阻？这不是一个标准值（374欧姆）。我计算输出电压为1.25 V * [ 1 +（187.5欧姆/ 240欧姆）] + 50×A* 187.5欧姆＝2.35 V。

以上来自于百度翻译


      以下为原文

     
Is your schematic for the LM317 circuit correct? 
 
How did your calculate that this circuit would have an output voltage of 3.3 V?
 
Have you measured the output voltage of the LM317 circuit?
 
Also, where did you get a 375 ohm resistor? That is not a standard value (374 ohm is).
 
I calculate the output voltage as 1.25 V * [1 + (187.5 ohm/240 ohm)] + 50 µA * 187.5 ohm = 2.35 V
 
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郑雅颖

2018-9-18 15:13:00
你真的有MPU的VCAP引脚连接到VDD电源轨作为您的示意图显示？这是一个很大的NO.NO（数据表的第2.3部分，DS7000，Vcap），如果你不能在没有施加电压的情况下对Vcap进行调试，那么我认为Vcap是不够的。（必须具有低ESR；我使用10μF，16V MLCC）。[编辑]如果Vcc是在规格，它没有正确地运行（生产或调试），也许临时桥额外电容器（S）跨越C5。这提供更多的电容和更低的ESR。我曾经为一个拥有未知来源钽的客户董事会做过这件事。[编辑]问候戴夫

以上来自于百度翻译


      以下为原文

   


Do you really have the MPU's Vcap pin connected to the Vdd power rail as your schematic shows?  That's a big no-no.  (Section 2.3 of the Data Sheet, DS70000657H)
 
If you can't debug without dinking with the voltage applied to Vcap, then I'm thinking that Vcap is inadequate.  (Must have low ESR; I use 10 uF, 16V MLCC.)
[Edit]
If Vcc is in spec and it isn't operating properly (producition or debug), maybe temporarily bridge extra capacitor(s) across C5.  This gives more capacitance and lower ESR.  I once did this for a client's board that had a Tantalum of unknown provenance.
[/Edit]
 
Regards,
 
Dave
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李天竹

2018-9-18 15:28:10
VCAP是内部电压调节器的输出。它比VDD少一些PICS有2.5V（你的可能是其中之一），其他的是1.8V。如果你用更高的电压（这种情况下的VDD）来增加它，它最终会炸开PIC.IFVCAP PUNEN不能自己产生所需的电压，你有VDD或电容器的问题。

以上来自于百度翻译


      以下为原文

    VCAP is the output of internal voltage regulator. It is less than VDD - some PICs have 2.5V (yours is likely one of them), others 1.8V. If you zap it with higher voltage (VDD in this case), it will eventually fry the PIC.
 
If VCAP pin doesn't produce the required voltage by itself, you have a problem with VDD or with capacitor.
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王璨

2018-9-18 15:45:07
有趣的是，EP生存了这么长时间。总结同事的发现：LM317的输出电压太低。（虽然LM317本身是一个合理的选择。）太低的电压（显然到现在为止还没有被发现）没有给芯片上的调节器足够的净空，从而在VCAP上产生稳定的电压。您的“补救”将VCAP连接到您的“3.3 V”电源（显然不高到足以立即杀死EP）。是重复故障的原因：你正在炸薯片随着时间的推移。补救：删除Vcap和你的3.3伏电源之间的连接。测量你的3.3伏电源，使它真正的3.3 V（或在范围3的东西…3.6 V）：删除R6- R8。如果我没有误算，对于R7和240欧姆的R7和3.2欧姆的37 X欧姆应该会产生一个很好的3.2 V -至少是好的开始。现在你可以自由地替换EP了。祝它长寿…

以上来自于百度翻译


      以下为原文

    Funny thing that the EP survives that long.
To summarize the colleagues' findings:

  • The output voltage of the LM317 is too low. (While the LM317 in itself is a reasonable choice.)
  • The too-low voltage (obviously gone undetected until now) didn't give the on-chip regulator enough headroom to create a stable voltage on Vcap.
  • Your "remedy" to connect Vcap to your "3.3 V" supply (obviously not high enough to kill the EP instantly) is the reason for the repeated failures: you're frying the chip over time.
Remedy:

  • Remove the connection between Vcap and your 3.3 V supply.
  • Measure your 3.3 V supply and make it really 3.3 V (or something in the range 3.0 .. 3.6 V): remove R6 - R8. If I did not miscalculate, 37x Ohms for R6 and 240 Ohms for R7 (leave R8 unpopulated) should result in a nice 3.2 V - at least good to start with.
  • Now you are free to replace the EP once again. Wish it a long life...
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