Email: Password: Remember Me | Create Account (Free)

Back to Subject List

Old thread has been locked -- no new posts accepted in this thread
???
03/15/07 01:22
Modified:
  03/15/07 02:32
Read: times


 		 #135021 - Exactly!
Responding to: ???'s previous message
Joseph said:
Reroute the trace so that it doesn't pass over the slot and your radiation will disappear.

Exactly!

Every single copper trace must be routed over the solid ground plane. Only by this the wave packets can undisturbedly propagate via the so formed transmission lines and the radiation is minimal, so minimal, that mostly you will not need additional shielding to meet the CE standards.

Joseph said:
This is a handy thing to understand if you ever have to deal with a split plane.

I have to every day! I do only (ONLY!) traverse the gap using a pi-low-pass-filter, with the serial component (resistor(s) or soft ferrite bead(s)) being "bend" over the gap like a bridge over a river AND with the caps sitting close to the gap, on both sides!

My last project using an AT89S52 in combination with a fast 8-channel-12bit-ADC and a RS485-interface was so properly filtered and shielded, that the EMC guy was asking me during the CE radiation test: "Is your device powered-on at all?", because he couldn't find any radiation.
The effective noise level on ADC inputs was less than 1/4LSB (300µV)!

Kai

List of 81 messages in thread
TopicAuthorDate
new PCB software wanted            01/01/70 00:00      
   If that is the case be happy, the more jumpe            01/01/70 00:00      
   Mike, when will you...            01/01/70 00:00      
      It isn't me            01/01/70 00:00      
         Four layer boards??            01/01/70 00:00      
            The only you get is a circuit >somwhat working<            01/01/70 00:00      
               sure, but he does not want to 'design' he wants to            01/01/70 00:00      
                  Connect A to B            01/01/70 00:00      
                     naah            01/01/70 00:00      
               are you sure you're not overstating your case?            01/01/70 00:00      
                  EMC issues            01/01/70 00:00      
                  As sure as one can be...            01/01/70 00:00      
                     All my commercial wire-wrap boards had 'em            01/01/70 00:00      
                        by Dr Howard Johnson and the like            01/01/70 00:00      
                           I don't think so ...            01/01/70 00:00      
                              so you DO think so            01/01/70 00:00      
                                 Well, yes and no ...            01/01/70 00:00      
                                    true, but how often have we seen            01/01/70 00:00      
                                       you can't FIX everything            01/01/70 00:00      
                                          not a word about lying            01/01/70 00:00      
                                             That would be a mistake            01/01/70 00:00      
                                                qualities often lacking            01/01/70 00:00      
                                                   Yes, and that's where the real lesson lies.            01/01/70 00:00      
                        Almost total agree...            01/01/70 00:00      
                           I don't think we entirely disagree, Kai ...            01/01/70 00:00      
                              Yes, less and less entire disagree...            01/01/70 00:00      
                     Slot antenna            01/01/70 00:00      
                        I think it's a loop, not so much a slot antenna            01/01/70 00:00      
                           Slot antennae            01/01/70 00:00      
                              Exactly!            01/01/70 00:00      
   "Target"            01/01/70 00:00      
      Free Target?            01/01/70 00:00      
         Identical            01/01/70 00:00      
            I found 1/2 the answer            01/01/70 00:00      
               why library for LCD?            01/01/70 00:00      
                  It doesn\'t require a library, just a decent editor            01/01/70 00:00      
               ??            01/01/70 00:00      
               In many respects, bEagle is probably the WORST            01/01/70 00:00      
                  I don't like Eagle either! It's not professional!            01/01/70 00:00      
                  hmm            01/01/70 00:00      
                     You may want to go back and read the comments            01/01/70 00:00      
                        I have given up to help Mike...            01/01/70 00:00      
                           I'm not stuck to eagle            01/01/70 00:00      
                              I would try to get a second hand win98 PC            01/01/70 00:00      
                                 He hasn't searched for drivers yet.            01/01/70 00:00      
                                    Not necessarily true...            01/01/70 00:00      
                                       not necessarily, but very likely            01/01/70 00:00      
                              You guys must like microsoft alot            01/01/70 00:00      
                                 ... and you're sure it doesn't emulate a laserjet?            01/01/70 00:00      
                                    stabile and relialbe ?!            01/01/70 00:00      
                                       Well the OS (XP in this case) doesn't type well            01/01/70 00:00      
                                          Stability            01/01/70 00:00      
                                             if it ain't broken...            01/01/70 00:00      
            Not Identical            01/01/70 00:00      
               Huh?            01/01/70 00:00      
                  Looks to me like it is just for hobby or            01/01/70 00:00      
                     What is your manufacturer?            01/01/70 00:00      
                        Sunstone Circuits            01/01/70 00:00      
                           Thanks            01/01/70 00:00      
               Identical refering to operation, of course!            01/01/70 00:00      
                  No, but            01/01/70 00:00      
                     much of?            01/01/70 00:00      
                        One thing he finally accepted ...            01/01/70 00:00      
         Ah, thanks :)            01/01/70 00:00      
      Wrong windows            01/01/70 00:00      
   See my other post...            01/01/70 00:00      
   see my pcb tutorial link in chat forum            01/01/70 00:00      
      What about the associated software?            01/01/70 00:00      
         No direct output            01/01/70 00:00      
         haven't tried it            01/01/70 00:00      
   There's a learning curve with any package            01/01/70 00:00      
      Link?            01/01/70 00:00      
         maybe that's why it still exists            01/01/70 00:00      
      Running on a Windoze box?            01/01/70 00:00      
         It works best on a DOS-box            01/01/70 00:00      
      without commenting on he wisdom            01/01/70 00:00      
         The DOS-OrCAD files import into Capture            01/01/70 00:00      
   Links to other Schematic/Layout software            01/01/70 00:00      
   A Guy in England            01/01/70 00:00      
   pcb software            01/01/70 00:00      
      PCB123            01/01/70 00:00      

Back to Subject List