KiCad is a suite of free software to design PCBs.[KiCad on Wikipedia]. I have been using it to make PCBs and it is OK so far. It is also easy to use. It comes with tools to check design rules and to produce Gerber files for manufacturing. I have written a getting started guide for KiCad in Myanmar language to take note about my experience and methods. And I combined them with English version guide which can be found on its website [Getting Started in KiCad, March 5, 2017]. My Myanmar version getting started guide for KiCad book can be found at
The above Figure shows a PCB which I designed using KiCad. It is a 8 layered PCB with the size of traces and clearance as narrow as 100 μm.
The dual core ARM microcontroller used in this PCB has WLCSP (wafer level chip-scale package) in 3 mm x 3 mm size with BGA (Ball Grid Array) footprint.
As a consequence, micro vias and blind vias with 100 μm in diameter have to be deployed in it.
A good thing about KiCad is that it automatically produces all the necessary drill files for all the pairs of layers for vias such as blind vias and embedded vias.
A stencil had to be made for soldering and assembling because of its complicated and tiny footprints.
When the first batch of assembled boards arrived, despite it was my very first time in designing a PCB using KiCad, they all work well.
The following one is another 4 layered PCB that I designed with KiCad to drive piezo actuators. It consists of 3 high voltage amplifiers that can produce more than 100 V. The resulting prototype boards also worked well in one shot. Thanks to rule check tools in KiCad.