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I found this on old CPU motherboard circuit and find its interesting.pic2 pic1 What is the purpose of that pattern? is it only for aesthetic or is there something else? I only seen the same pattern on bluetooth module rf antenna.

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  • \$\begingroup\$ So that two high-speed differential traces are the same length for phase (time delay) matching. \$\endgroup\$ Apr 21 '18 at 1:29
  • \$\begingroup\$ Probably wanted to add a little delay. Good question though. I've never seen that be done before but it's a very good chance that is the case. \$\endgroup\$
    – user103380
    Apr 21 '18 at 1:33
  • \$\begingroup\$ @KingDuken You'll find it everywhere where there is a DDR memory. \$\endgroup\$
    – user162889
    Apr 21 '18 at 1:44
  • \$\begingroup\$ There is an even older question, electronics.stackexchange.com/q/74789/117785 \$\endgroup\$ Apr 21 '18 at 1:44
  • \$\begingroup\$ sorry, I dont know proper keyword for this and ignorantly just search for "zigzag" keyword. I'll close the question by myself but seeing there's an answer already perhaps i'll just wait for the vote \$\endgroup\$
    – dpw
    Apr 21 '18 at 1:45
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Some electronic devices such as DDR memories transmit data at very high speed and traces that carry those signals are critical. The only point of that routing technique (leaving antennas and RF stuff apart) is to achieve the exact similar trace lengths in all of those signals. The zig zag allows to gain some millimeters when the straight path is too short for the target length. Same length in all of the data traces allows the data to arrive at almost the same time to the data pins and so, achieve better transmission rates and performance.

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