ESP8266 Community Forum

- Wed Jun 15, 2016 1:09 pm #49232 Thanks for all the advices, learning a lot of it in a new field for me
This forum is really full of great people wanting to help a newbe like me thanks!

on topic:

I thought any line with would be ok, since it's just 3.3v, but apparently I'm wrong. Is there any recommended size? Is there also any recommended clearance to use? I now didn't touch it in eagle.

I now also ran the error check in eagle, it actually told me there was a overlap

I now have the board running with the ESP on it, after cutting through the faulty line, and connecting the SCL up with a wire.

To get it punning was a bit of a pain, because the ESP12 that I was using was actually faulty (Or maybe it's more likely that I blew it up), vcc and gnd where shorted (desoldered the whole thing to figure that out).

I now have the HT7333 voltage regulators in. They're SOT-89 size instead of the SOT-223 size LM1117 that I was using. It will require some fiddling to get them on this board, but I'll have a try (doesn't seem the HT7333 is available as SOT-223)

- Wed Jun 15, 2016 1:59 pm #49239

I thought any line with would be ok, since it's just 3.3v, but apparently I'm wrong. Is there any recommended size?

The voltage does not really matter in this case, the current is the defining factor. Thinner traces have higher resistance, so according to Ohm's law, you will have a higher voltage drop across the trace.

The actual width depends on the current, the acceptable voltage drop and the allowed temperature rise of the trace. There are several online (and offline) tools available to calculate trace widths, such as http://www.desmith.net/NMdS/Electronics/TraceWidth.html

In your case, the width is indeed not very critical, since the current is rather low and the traces are short, but it's good to make it a habit to use thicker traces for VCC/GND.

Is there also any recommended clearance to use? I now didn't touch it in eagle.

That depends on your PCB fab, they should have minimum clearances specified on their website, some even provide DRC files that can be directly imported in eagle.

To get it punning was a bit of a pain, because the ESP12 that I was using was actually faulty (Or maybe it's more likely that I blew it up), vcc and gnd where shorted (desoldered the whole thing to figure that out).

Given the level of quality control (or rather lack thereof) on these 2-3$ boards, a faulty module would not surprise me...
The most likely cause of a short would be actually be the metal shield covering the module, it's placed pretty close to some of the components. Your module might work if you remove the can.

I now have the HT7333 voltage regulators in. They're SOT-89 size instead of the SOT-223 size LM1117 that I was using. It will require some fiddling to get them on this board, but I'll have a try (doesn't seem the HT7333 is available as SOT-223)

Good news is, that SOT-89 will fit on the back of those white ESP-12 breakout boards, in case you have some of those.