Why you should consider .8mm PCBs over 1.6mm PCBs?
Hello, I'm working on an article about why you should consider .8mm PCBs over 1.6mm PCBs (mostly in the context of 2-layer boards). Anything I should mention?
I'm not advocating that in all cases over 1.6mm thickness, but seems like something that beginners especially wouldn't even consider I think the most obvious factors are weight, volume, and cost, but I know captive issues come into play as well. Any insight/references on capacitance that I should look at?
Also I saw some mention of how it affects solder joint fatigue, would welcome your thoughts on that too!
6 Replies
Actually, one thing I'd looked at a while ago is the RP2040 design guide https://datasheets.raspberrypi.com/rp2040/hardware-design-with-rp2040.pdf, section 2.4.1, where it talks about the differential impedance for the USB spec and having a ground plane nearby. Not certain if the distance to the ground plane actually affects characteristic impedance, or if that is a separate solution for minimizing crosstalk. Thoughts?
The ground plane affects the impedance of the differential pair. The closer the ground plane is, the higher the capacitance and the lower the impedance.
In terms of impedence characteristics, 1.6mm will have larger width size compared to .8mm.
I recommend using some calc to verify the numbers.
Ya he should. It also depends on the application,
We can ask @Chimmuanya Okere for the input because she has worked on many designs and collected piles of information.