The quick way:
- Before you start your design, go to:
- Click on the question mark next to “Layers”;
- Read the page that opens;
- Select 4 or 6 layers;
- Click on the question mark next to “Impedance”;
- Read the page that opens;
- Select “Yes”;
- Click on “Impadance calculator”;
- Choose your desired transmission line structure (single ended or differential covered microstrip, inner layer stripline, offset stripline);
- use the calculator and note the trace dimensions.
- Following the Design Flow in the Tutorial, start your design in the Schematic Editor of EasyEDA and then convert it to a PCB, then manually route your layout using the calculated trace dimensions.
The longer way for 4 and 6 layer PCBs only:
- Before you start your design, read “Controlled Impedance PCB” in:
https://jlcpcb.com/capabilities/Capabilities;
- Choose your PCB stack up:
https://jlcpcb.com/quote/pcbOrderFaq/PCB%20Stackup
or:
https://jlcpcb.com/client/index.html#/impedance;
- Choose your desired transmission line structure (single ended or differential covered microstrip, inner layer stripline, offset stripline);
- then use:
https://jlcpcb.com/client/index.html#/impedanceCalculation
- use the calculator and note the trace dimensions.
- Following the Design Flow in the Tutorial, start your design in the Schematic Editor of EasyEDA and then convert it to a PCB, then manually route your layout using the calculated trace dimensions.
The more detailed and flexible way but which will not be covered by any warranty from JLCPCB:
- Install a copy of a simple field solver impedance calculator:
https://www.maartenbaert.be/alterpcb/tlinesim/
https://sourceforge.net/projects/mdtlc/files/development/0_2_1_dev/
or:
https://sourceforge.net/projects/mmtl/files/tnt/1.2.2/
- Choose your PCB stackup:
https://jlcpcb.com/client/index.html#/impedance
- Then use their figures as inputs to the field solver to calculate the trace widths and spacings for your desired transmission line structure (bare microstrip, covered microstrip, buried microstrip, symmetrical stripline, offset stripline, differential variants of microstrip and striplines,coplanar wiveguide, etc. etc.)
- Note the trace dimensions.
- Following the Design Flow in the Tutorial, start your design in the Schematic Editor of EasyEDA and then convert it to a PCB, then manually route your layout using the calculated trace dimensions.
- Note that:
(i) for 2 layer PCBs the information provided about the PCB material is incomplete;
(ii) using tools and stack ups other than those specified by JLCPCB will almost certainly void any claim against them for the resulting PCB failing to the target impedance.
Source: Forum – EasyEDA – An Easier Electronic Circuit Design Experience – EasyEDA