Connecting top and bottom SMD component pads using viaEagle is refusing to tie ground pads of SMD components...

Why would a flight no longer considered airworthy be redirected like this?

Font with correct density?

PTIJ: Who should pay for Uber rides: the child or the parent?

What options are left, if Britain cannot decide?

Using "wallow" verb with object

Why must traveling waves have the same amplitude to form a standing wave?

Do I need life insurance if I can cover my own funeral costs?

2D counterpart of std::array in C++17

How to generate globally unique ids for different tables of the same database?

Rules about breaking the rules. How do I do it well?

Professor being mistaken for a grad student

My adviser wants to be the first author

Why does Deadpool say "You're welcome, Canada," after shooting Ryan Reynolds in the end credits?

How to simplify this time periods definition interface?

Welcoming 2019 Pi day: How to draw the letter π?

Can elves maintain concentration in a trance?

Have researchers managed to "reverse time"? If so, what does that mean for physics?

Meaning of "SEVERA INDEOVI VAS" from 3rd Century slab

Good allowance savings plan?

How could a female member of a species produce eggs unto death?

Fill color and outline color with the same value

Make a transparent 448*448 image

Replacing Windows 7 security updates with anti-virus?

Ban on all campaign finance?



Connecting top and bottom SMD component pads using via


Eagle is refusing to tie ground pads of SMD components to the ground planeDipTrace bottom layer pad shapeEagle configure autorouter to solder components (except vias) only on bottom layer of double sided PCBIs every pad in eagle a via?Eagle: polygon pour leaving funny blank areasRouting and placement of decoupling capacitor when using power planeA confusion on using PCB copper pourPlacing the pads of SMD components in different layers (KiCad PCB design)How to prevent tombstoning using via-in-pad with small SMD discretesPastemask for through hole components













3












$begingroup$


I am working on a 2 layer board and the PCB will be a double sided job. Some components on the top layer will have exact mirrors on the bottom right under them. My question is, for SMD components, can I just connect those pads with a via right in the center of the pads?



Does this affect electrical performance or production/assembly in any shape or form?



The reason: The bottom layer is a copper pour for ground and I have pads that belong to GND net so why not?



Please see the picture below (for demonstration porpuses I have moved the top component a little bit higher).



P.S. The components are TVS diodes (SM8J36CA). But my qustion is more general and is about wherever the pad size allows hosting a via in its center!



enter image description here










share|improve this question











$endgroup$








  • 2




    $begingroup$
    Talk to whoever is doing your assembly. Vias-in-pads generally wick solder away from the joint, causing reliability issues.
    $endgroup$
    – Dave Tweed
    3 hours ago






  • 2




    $begingroup$
    I wouldn't try it due to issues that can arise. They do this on BGAs where space is at a premium and it's called "via-in-pad" but they take special measures to make sure it works.
    $endgroup$
    – Toor
    3 hours ago






  • 2




    $begingroup$
    It's possible, but not recommended. If you're hand-assembling them, it should be okay, if a little harder to keep together. If this is for automated assembly, don't do it unless you really have no other option.
    $endgroup$
    – Hearth
    3 hours ago
















3












$begingroup$


I am working on a 2 layer board and the PCB will be a double sided job. Some components on the top layer will have exact mirrors on the bottom right under them. My question is, for SMD components, can I just connect those pads with a via right in the center of the pads?



Does this affect electrical performance or production/assembly in any shape or form?



The reason: The bottom layer is a copper pour for ground and I have pads that belong to GND net so why not?



Please see the picture below (for demonstration porpuses I have moved the top component a little bit higher).



P.S. The components are TVS diodes (SM8J36CA). But my qustion is more general and is about wherever the pad size allows hosting a via in its center!



enter image description here










share|improve this question











$endgroup$








  • 2




    $begingroup$
    Talk to whoever is doing your assembly. Vias-in-pads generally wick solder away from the joint, causing reliability issues.
    $endgroup$
    – Dave Tweed
    3 hours ago






  • 2




    $begingroup$
    I wouldn't try it due to issues that can arise. They do this on BGAs where space is at a premium and it's called "via-in-pad" but they take special measures to make sure it works.
    $endgroup$
    – Toor
    3 hours ago






  • 2




    $begingroup$
    It's possible, but not recommended. If you're hand-assembling them, it should be okay, if a little harder to keep together. If this is for automated assembly, don't do it unless you really have no other option.
    $endgroup$
    – Hearth
    3 hours ago














3












3








3





$begingroup$


I am working on a 2 layer board and the PCB will be a double sided job. Some components on the top layer will have exact mirrors on the bottom right under them. My question is, for SMD components, can I just connect those pads with a via right in the center of the pads?



Does this affect electrical performance or production/assembly in any shape or form?



The reason: The bottom layer is a copper pour for ground and I have pads that belong to GND net so why not?



Please see the picture below (for demonstration porpuses I have moved the top component a little bit higher).



P.S. The components are TVS diodes (SM8J36CA). But my qustion is more general and is about wherever the pad size allows hosting a via in its center!



enter image description here










share|improve this question











$endgroup$




I am working on a 2 layer board and the PCB will be a double sided job. Some components on the top layer will have exact mirrors on the bottom right under them. My question is, for SMD components, can I just connect those pads with a via right in the center of the pads?



Does this affect electrical performance or production/assembly in any shape or form?



The reason: The bottom layer is a copper pour for ground and I have pads that belong to GND net so why not?



Please see the picture below (for demonstration porpuses I have moved the top component a little bit higher).



P.S. The components are TVS diodes (SM8J36CA). But my qustion is more general and is about wherever the pad size allows hosting a via in its center!



enter image description here







pcb pcb-design analog pcb-fabrication pcb-assembly






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited 2 hours ago









JRE

22.2k43771




22.2k43771










asked 3 hours ago









Sean87Sean87

1,543123360




1,543123360








  • 2




    $begingroup$
    Talk to whoever is doing your assembly. Vias-in-pads generally wick solder away from the joint, causing reliability issues.
    $endgroup$
    – Dave Tweed
    3 hours ago






  • 2




    $begingroup$
    I wouldn't try it due to issues that can arise. They do this on BGAs where space is at a premium and it's called "via-in-pad" but they take special measures to make sure it works.
    $endgroup$
    – Toor
    3 hours ago






  • 2




    $begingroup$
    It's possible, but not recommended. If you're hand-assembling them, it should be okay, if a little harder to keep together. If this is for automated assembly, don't do it unless you really have no other option.
    $endgroup$
    – Hearth
    3 hours ago














  • 2




    $begingroup$
    Talk to whoever is doing your assembly. Vias-in-pads generally wick solder away from the joint, causing reliability issues.
    $endgroup$
    – Dave Tweed
    3 hours ago






  • 2




    $begingroup$
    I wouldn't try it due to issues that can arise. They do this on BGAs where space is at a premium and it's called "via-in-pad" but they take special measures to make sure it works.
    $endgroup$
    – Toor
    3 hours ago






  • 2




    $begingroup$
    It's possible, but not recommended. If you're hand-assembling them, it should be okay, if a little harder to keep together. If this is for automated assembly, don't do it unless you really have no other option.
    $endgroup$
    – Hearth
    3 hours ago








2




2




$begingroup$
Talk to whoever is doing your assembly. Vias-in-pads generally wick solder away from the joint, causing reliability issues.
$endgroup$
– Dave Tweed
3 hours ago




$begingroup$
Talk to whoever is doing your assembly. Vias-in-pads generally wick solder away from the joint, causing reliability issues.
$endgroup$
– Dave Tweed
3 hours ago




2




2




$begingroup$
I wouldn't try it due to issues that can arise. They do this on BGAs where space is at a premium and it's called "via-in-pad" but they take special measures to make sure it works.
$endgroup$
– Toor
3 hours ago




$begingroup$
I wouldn't try it due to issues that can arise. They do this on BGAs where space is at a premium and it's called "via-in-pad" but they take special measures to make sure it works.
$endgroup$
– Toor
3 hours ago




2




2




$begingroup$
It's possible, but not recommended. If you're hand-assembling them, it should be okay, if a little harder to keep together. If this is for automated assembly, don't do it unless you really have no other option.
$endgroup$
– Hearth
3 hours ago




$begingroup$
It's possible, but not recommended. If you're hand-assembling them, it should be okay, if a little harder to keep together. If this is for automated assembly, don't do it unless you really have no other option.
$endgroup$
– Hearth
3 hours ago










1 Answer
1






active

oldest

votes


















4












$begingroup$


I am working on a 2 layer board and the PCB will be a double sided
job. Some components on the top layer will have exact mirrors on the
bottom right under them. My question is, for SMD components, can I
just connect those pads with a VIA right in the center of the pads?




Yes, will the assembly house be happy about it? No. Vias wick solder through them, plus using a stencil will apply the wrong amount of solder for the component because most of it will be in the hole.



If you do this, let the assembly house know (or if your hand soldering them who cares?) They will probably need to hand solder this component.




Does this affect electrical performance or production/assembly in any
shape or form?




If the signals in question aren't running at the +50Mhz speed then no, a few nH of inductance isn't going to make a difference. Vias might slow down very fast ESD events, if this is the only inductor in the current path which is unlikely. if adding a 10's of nH to the design makes a difference then run a PCB via inductance calculator and parallel the vias or do something else.






share|improve this answer









$endgroup$













    Your Answer





    StackExchange.ifUsing("editor", function () {
    return StackExchange.using("mathjaxEditing", function () {
    StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
    StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["\$", "\$"]]);
    });
    });
    }, "mathjax-editing");

    StackExchange.ifUsing("editor", function () {
    return StackExchange.using("schematics", function () {
    StackExchange.schematics.init();
    });
    }, "cicuitlab");

    StackExchange.ready(function() {
    var channelOptions = {
    tags: "".split(" "),
    id: "135"
    };
    initTagRenderer("".split(" "), "".split(" "), channelOptions);

    StackExchange.using("externalEditor", function() {
    // Have to fire editor after snippets, if snippets enabled
    if (StackExchange.settings.snippets.snippetsEnabled) {
    StackExchange.using("snippets", function() {
    createEditor();
    });
    }
    else {
    createEditor();
    }
    });

    function createEditor() {
    StackExchange.prepareEditor({
    heartbeatType: 'answer',
    autoActivateHeartbeat: false,
    convertImagesToLinks: false,
    noModals: true,
    showLowRepImageUploadWarning: true,
    reputationToPostImages: null,
    bindNavPrevention: true,
    postfix: "",
    imageUploader: {
    brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
    contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
    allowUrls: true
    },
    onDemand: true,
    discardSelector: ".discard-answer"
    ,immediatelyShowMarkdownHelp:true
    });


    }
    });














    draft saved

    draft discarded


















    StackExchange.ready(
    function () {
    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2felectronics.stackexchange.com%2fquestions%2f427294%2fconnecting-top-and-bottom-smd-component-pads-using-via%23new-answer', 'question_page');
    }
    );

    Post as a guest















    Required, but never shown

























    1 Answer
    1






    active

    oldest

    votes








    1 Answer
    1






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    4












    $begingroup$


    I am working on a 2 layer board and the PCB will be a double sided
    job. Some components on the top layer will have exact mirrors on the
    bottom right under them. My question is, for SMD components, can I
    just connect those pads with a VIA right in the center of the pads?




    Yes, will the assembly house be happy about it? No. Vias wick solder through them, plus using a stencil will apply the wrong amount of solder for the component because most of it will be in the hole.



    If you do this, let the assembly house know (or if your hand soldering them who cares?) They will probably need to hand solder this component.




    Does this affect electrical performance or production/assembly in any
    shape or form?




    If the signals in question aren't running at the +50Mhz speed then no, a few nH of inductance isn't going to make a difference. Vias might slow down very fast ESD events, if this is the only inductor in the current path which is unlikely. if adding a 10's of nH to the design makes a difference then run a PCB via inductance calculator and parallel the vias or do something else.






    share|improve this answer









    $endgroup$


















      4












      $begingroup$


      I am working on a 2 layer board and the PCB will be a double sided
      job. Some components on the top layer will have exact mirrors on the
      bottom right under them. My question is, for SMD components, can I
      just connect those pads with a VIA right in the center of the pads?




      Yes, will the assembly house be happy about it? No. Vias wick solder through them, plus using a stencil will apply the wrong amount of solder for the component because most of it will be in the hole.



      If you do this, let the assembly house know (or if your hand soldering them who cares?) They will probably need to hand solder this component.




      Does this affect electrical performance or production/assembly in any
      shape or form?




      If the signals in question aren't running at the +50Mhz speed then no, a few nH of inductance isn't going to make a difference. Vias might slow down very fast ESD events, if this is the only inductor in the current path which is unlikely. if adding a 10's of nH to the design makes a difference then run a PCB via inductance calculator and parallel the vias or do something else.






      share|improve this answer









      $endgroup$
















        4












        4








        4





        $begingroup$


        I am working on a 2 layer board and the PCB will be a double sided
        job. Some components on the top layer will have exact mirrors on the
        bottom right under them. My question is, for SMD components, can I
        just connect those pads with a VIA right in the center of the pads?




        Yes, will the assembly house be happy about it? No. Vias wick solder through them, plus using a stencil will apply the wrong amount of solder for the component because most of it will be in the hole.



        If you do this, let the assembly house know (or if your hand soldering them who cares?) They will probably need to hand solder this component.




        Does this affect electrical performance or production/assembly in any
        shape or form?




        If the signals in question aren't running at the +50Mhz speed then no, a few nH of inductance isn't going to make a difference. Vias might slow down very fast ESD events, if this is the only inductor in the current path which is unlikely. if adding a 10's of nH to the design makes a difference then run a PCB via inductance calculator and parallel the vias or do something else.






        share|improve this answer









        $endgroup$




        I am working on a 2 layer board and the PCB will be a double sided
        job. Some components on the top layer will have exact mirrors on the
        bottom right under them. My question is, for SMD components, can I
        just connect those pads with a VIA right in the center of the pads?




        Yes, will the assembly house be happy about it? No. Vias wick solder through them, plus using a stencil will apply the wrong amount of solder for the component because most of it will be in the hole.



        If you do this, let the assembly house know (or if your hand soldering them who cares?) They will probably need to hand solder this component.




        Does this affect electrical performance or production/assembly in any
        shape or form?




        If the signals in question aren't running at the +50Mhz speed then no, a few nH of inductance isn't going to make a difference. Vias might slow down very fast ESD events, if this is the only inductor in the current path which is unlikely. if adding a 10's of nH to the design makes a difference then run a PCB via inductance calculator and parallel the vias or do something else.







        share|improve this answer












        share|improve this answer



        share|improve this answer










        answered 2 hours ago









        laptop2dlaptop2d

        26.3k123381




        26.3k123381






























            draft saved

            draft discarded




















































            Thanks for contributing an answer to Electrical Engineering Stack Exchange!


            • Please be sure to answer the question. Provide details and share your research!

            But avoid



            • Asking for help, clarification, or responding to other answers.

            • Making statements based on opinion; back them up with references or personal experience.


            Use MathJax to format equations. MathJax reference.


            To learn more, see our tips on writing great answers.




            draft saved


            draft discarded














            StackExchange.ready(
            function () {
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2felectronics.stackexchange.com%2fquestions%2f427294%2fconnecting-top-and-bottom-smd-component-pads-using-via%23new-answer', 'question_page');
            }
            );

            Post as a guest















            Required, but never shown





















































            Required, but never shown














            Required, but never shown












            Required, but never shown







            Required, but never shown

































            Required, but never shown














            Required, but never shown












            Required, but never shown







            Required, but never shown







            Popular posts from this blog

            Фонтен-ла-Гаярд Зміст Демографія | Економіка | Посилання |...

            Список ссавців Італії Природоохоронні статуси | Список |...

            Маріан Котлеба Зміст Життєпис | Політичні погляди |...