9 Replies Latest reply on Jan 24, 2017 7:49 PM by malgumhasan@gmail.com

    A easy layout justification !

    malgumhasan@gmail.com

      Hello Everyone,

       

      I am trying to design a simple pcb layout of a schmitt-trigger as follows,

      schmitt-trigger-using-ne-555.JPG

       

       

      After creating the schematic I have accessed to Layout and router, take a look top and bottom view, if anything need to modify, kindly let me know.

      top_bot_pads.png

        • 1. Re: A easy layout justification !
          Jack

          I'm not familiar with PADs, but since you asked for help,

          I would first say that the purpose of this forum is traditionally been to discuss software issues, not design issues.

          (You probably won't get much help from here on PCB design principles.)

          In fact, I don't know ANYWHERE that you can get a design checked online,

          (maybe I should start a "review" service? hmmm... )

          anyway, If you need to learn more about circuit board design, try:

          HowToPCB.net
          or
          How To PCB

          Regarding the images above, if the RED is supposed to be copper,

          - I can't see that it is connecting to anything, make sure it is assigned to a net like GND or PWR

            (J1/J3 pin 2, for example)

          - it looks very close to other features, maybe you should increase the clearance from pads/traces to fills

          - if you are pouring copper planes on both sides, make one PWR and the other GND, then you can remove some of those traces

          (not sure of the PADs terminology for planes, copper pours, area fills - all means the same thing)

          1 of 1 people found this helpful
          • 2. Re: A easy layout justification !
            malgumhasan@gmail.com

            Dear Sir Jack,

             

            So kind of you! Thank you to put your time here.

            At least If I could talk to you, I will learn something.

            Lets take your website as ideal one!

             

            I can't see that it is connecting to anything, make sure it is assigned to a net like GND or PWR

            Well said, for the adding copper pour in PCB, I have used this options

            add_draft.PNG

             

             

             

             

             

             

             

             

             

             

             

             

             

             

             

             

             

             

             

            To connect a layer with GND, what I did is

            Selecting Top from the Layer dropdown list and GND from the Net assignment

            dropdown list. I thought an external PWR can be provide from J3, Ooops its wrong, I may need another Header!

             

             

            it looks very close to other features, maybe you should increase the clearance from pads/traces to fills

            May be it needs to explore this software, what actually means ? Can you explain it more?

             

            if you are pouring copper planes on both sides, make one PWR and the other GND, then you can remove some of those traces

            Dont you mean, I need to make another layer for PWR? Does it look 2 PWR from 2 layers?  Which traces you mentioned ?

            • 3. Re: A easy layout justification !
              malgumhasan@gmail.com

              Dear Sir Jack,

               

              Dont you talking about Design Rules in PADs layout?

              Take a look this view,

              design_rules.PNG

              • 4. Re: A easy layout justification !
                Jack

                I have never used PADs software. I can't help you.

                Look for a Tutorial or a "Getting Started" lesson somewhere

                (there used to be a PADS User Group online forum that was independent of Mentor. maybe it still exists?)

                best wishes,
                Jack

                1 of 1 people found this helpful
                • 5. Re: A easy layout justification !
                  malgumhasan@gmail.com

                  Thank you sir Jack.

                  What other software you have used ? OrCAD or Eagle?

                  there used to be a PADS User Group online forum that was independent of Mentor. maybe it still exists?)

                  Its started in 2010, looks inactive now a days.

                  Look for a Tutorial or a "Getting Started" lesson somewhere

                  I got some good introduction for basic setting of PCB design.

                  I can make them on PADS, but need criticism to evaluate my design.

                  • 6. Re: A easy layout justification !
                    Jack

                    started on PCAD for DOS in 1987, moved to AccelEDA when Windows kicked in, cheerfully learned Veribest at a new job, (renamed to Expedition when Mentor bought Veribest), went backwards to Mentor BoardStation when I moved to Illinois, (but fortunately had access to AutoActiveRE for the last 15 years!). Now we are finally making the transition to Expedition

                     

                    I only stumbled into this area accidentally, when I saw someone was asking about minimum drill sizes

                    • 7. Re: A easy layout justification !
                      malgumhasan@gmail.com

                      Its true  that, you know pcb design foundation.

                      No matter what PADS9.5 or OrCAD do!

                       

                      For a newborn baby designer, what books you would suggest beside your website?

                      Pdf material is fine.

                      • 8. Re: A easy layout justification !
                        Jack

                        I don't know of any books on PCB design. That's why I made the website.

                         

                        There is a lot of good info in "Printed Circuits Handbook", but it is not specifically about design

                        (it also covers just about every aspect of PCB fabrication, assembly, test, etc)

                         

                        Do you subscribe to the PCB Design magazines?

                        I-Connect007 :: Design Magazine

                        1 of 1 people found this helpful
                        • 9. Re: A easy layout justification !
                          malgumhasan@gmail.com

                          I see, lets study more.

                          I have not try for this magazine, does it every volume cover pcb design stuff?