Connect with us

6 layer pcb stack

Discussion in 'PCB Layout, Design and Manufacture' started by Rajinder, Nov 13, 2016.

  1. Rajinder

    Rajinder

    399
    7
    Jan 30, 2016
    Hi all,
    I have a coupe of questions:
    i have a 6 layer pcb, the stack up is as follows

    layer 1 - component (smd and through-hole) + tracking of analogue signals
    layer 2 - gnd
    layer 3 - inner track for digital signals i.e. spi, i2c
    layer 4- inner track for digital signals i.e. spi, i2c
    layer 5 - power i.e. 5v and 3v3
    layer 6 - tracking low frequency signals - led driving

    ideally i wanted to layer 4 as another gnd layer but couldnt do this due alot of componenets that needed to be tracked.

    Please could some one explain if i need to stitch areas of copper to 0v from layers 4 and 6?
    please could someone explain the difference between 1oz and 2oz copper i.e. what it means in terms of pcb design

    thanks in advance
     
  2. (*steve*)

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    25,178
    2,690
    Jan 21, 2010
    1 oz copper is 1 oz per square foot. 2 oz copper is twice as thick and can this carry twice the current.
     
  3. AnalogKid

    AnalogKid

    2,297
    646
    Jun 10, 2015
    Thicker copper has lower resistance for the same trace width, and can carry more current for the same temperature increase. There are online calculators for this. It is not a linear relationship because thicker copper also has more overetching or etch undercut, which decreases the effective cross-sectional area.

    Thicker copper also has a different characteristic impedance for stripline and microstripline designs, and there are online calculators for this. In general, very high frequency designs such as gigabit Ethernet perform better with thinner copper layers, such as 1/2 oz.

    ak
     
    (*steve*) likes this.
  4. Arul Raju

    Arul Raju

    28
    2
    Mar 5, 2014
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-