October 1, 2016, 6:10 am
I’ve just finished the first revision of the esp32 version of the espusb stick and it’s now out to fab. I expect to have to do at least some rework and probably a couple more iterations before I’m happy with it. But if you want to hack around with it, the Kicad files and gerbers are below.
As before the board contains a ch340g usb interface, buck converter (to generate 3.3v efficiently) and an SD card slot as well as the esp32. I have exactly one esp32 IC at the moment… so it might take some time to get this board up an running.
This is also currently a 2 layer board, I think this should be fine, but it’s possible I’ll need to rework it as a 4 layer design at some point.
Once I have a revision I’m comfortable it’ll go in the shop. If you’d like to pre-order it, let me know. For a hand assembled board it’ll probably be 20USD. Plug: if you buy stuff from my shop it makes it more likely that I’ll be able to get a production run done and put out a cheaper version.
Kicad files and Gerbers: esp32_usb
September 29, 2016, 6:04 pm
I’m starting a esp32 design as a possible migration path from the esp8266 based espusb. The esp32 is currently low availability, and is a much more expensive part, but figured I’d give it a crack. First up, a schematic symbol. I hate how long these things take, and that they rarely get shared, so here’s mine (download below).
Download here (contains esp32.lib): esp32lib
September 29, 2016, 3:22 pm
Espressif kindly provide the schematics and layout files for the esp32 based WROOM32. In preparation for my own design (based on my espusb) I’ve been looking over these files.
The zip file they provide (local copy) contains 
design files in a variety of formats. The source .PCB and .SCH files appear to be included, but there are no notes and I couldn’t determine which tool they are for (if you know please comment – my best guess is OrCAD). They also include pdf printouts of the schematic and and layout. The Layout pdf is reproduced to the right. However, it doesn’t show any of the silk and only appears to be the top copper layer. I therefore generated the image above from the gerbers that are also included.
The gerbers also don’t use a naming convention I’m familiar with, but from what I can tell the WROOM32 is a 4 layer board. I’m kind of surprised that they didn’t try and squeeze everything onto 2 layers, like they do with the esp1. Will be interesting to see if the esp32 also forces me to start doing 4 layer designs.
For reference, the BOM and schematic are below:
September 28, 2016, 5:04 pm
I’ve been playing with a new esp8266 design. The board has 2 esp8266s on one PCB. It’s based around my espusb design.
The board contains a ch340g usb interface, an MSP1603 buck converter to power the 2 esp8266s. The SPI buses of the esps are linked so that they can communicate. There are headers that allow the 2 esps to be programmed independently.
One idea of course is that I could uses these boards to build a basic mesh network. I think they’ll be fun to play around with in any case. Gerbers and Kicad files below. If boards work, and there’s any interest, I might stick them in my shop. If you think you’d like one email me ([email protected]).
Kicad design files and gerbers: espusb_dual
RSS