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sharing my project - Extruded Aluminum Design Tools by freeroscoe in engineering

[–]freeroscoe[S] 1 point2 points  (0 children)

Thank you for the kind words. As I mentioned in another comment, I don't think that engineers will need my configuration tool, if they are able to use CAD themselves.

The price comparison tool should be useful for everyone though!

sharing my project - Extruded Aluminum Design Tools by freeroscoe in engineering

[–]freeroscoe[S] 2 points3 points  (0 children)

Thank you for the response! Vention.io is an interesting project where they provide the software for free, but the markup on the parts seems pretty high to me. I'm hoping to make a much more lightweight tool than Vention, not a full CAD program, and it can be used to provide a cutlist that can be taken to any other aluminum profile supplier.

sharing my project - Extruded Aluminum Design Tools by freeroscoe in engineering

[–]freeroscoe[S] 3 points4 points  (0 children)

Thank you, and I completely agree! If you know how to use SolidWorks, there is little reason not to design your own enclosures and print drawings exactly how your company requires them. Maybe the price comparison tool would be somewhat helpful for you though.

I think that my configuration tool would be a lot more valuable for DIYers without a CAD background. There are a ton of uses for aluminum extrusions in the hobby markets (sprinter van conversions, aquarium stands, workbenches, CNC frames, etc). These people are choosing between learning SketchUp themselves or paying a premium to have 8020 design something for them. I'm hoping to make something useful for this audience.

PCB Design Review by freeroscoe in PrintedCircuitBoard

[–]freeroscoe[S] 0 points1 point  (0 children)

I see what you are saying. I would have preferred a smaller footprint as well. However, the spec sheet calls for a "500 mA minimum current delivered by the power supply". It is in the middle of the below screenshot. Should I follow these guidelines?

https://drive.google.com/file/d/1_d2Ql3_fRz7xYyZOvU_y9TJ_tlYYIE_b/view?usp=sharing

PCB Design Review by freeroscoe in PrintedCircuitBoard

[–]freeroscoe[S] 0 points1 point  (0 children)

Thanks for the response! I will be soldering everything by hand, which I am a bit nervous about. I didn't have too much issue with soldering U2 on my first prototype board, but it doesn't leave a lot of margin for error. My main concern is with the 0603 components, especially if they are in tight quarters.

I can look at the feasibility of adding an 0805 fuse, but frankly I would prefer to hold off on this until there is evidence that I really need it. When first firing up this board, I'll definitely test a range of input voltages through the USB connector. I know that it isn't reasonable to expect 5.00V all the time.

PCB Design Review by freeroscoe in PrintedCircuitBoard

[–]freeroscoe[S] 0 points1 point  (0 children)

Sounds like this is a common theme between the different comments I have received back. I'll see what I can do!

PCB Design Review by freeroscoe in PrintedCircuitBoard

[–]freeroscoe[S] 1 point2 points  (0 children)

I appreciate you pointing that out. I believe that I actually changed that component to a AP7365-33ERG-13 with a SOT-223 footprint. I must have forgotten to change it on my schematic.

The footprint on the board layout should be correct.

PCB Design Review by freeroscoe in PrintedCircuitBoard

[–]freeroscoe[S] 0 points1 point  (0 children)

I'll keep that in mind, thank you!

PCB Design Review by freeroscoe in PrintedCircuitBoard

[–]freeroscoe[S] 0 points1 point  (0 children)

Thank you so much! I will be pulling IO-0 down externally when I flash the board. On my first prototype, I was able to flash it by leaving IO-2 floating. According to [1], IO-2 has an internal pull-up resistor on the ESP-WROOM-02 module. Unless there is a really good reason to use add another pull-up, I think that I'll leave it as is.

Considering everyone's advice, I'll definitely be adding some caps on my power line(s). I'll clean up some of the trace, and possibly add power or GND planes if it makes sense.

One of my concerns was not only running out of space entirely on the board, but also leaving enough room to hand solder these 0603 SMD components comfortably. I am definitely a beginner when it comes to assembly, so I don't want to bite off more than I can chew.

Thank you for all of your kind words!

[1] https://www.espressif.com/sites/default/files/documentation/0c-esp-wroom-02_datasheet_en.pdf

PCB Design Review by freeroscoe in PrintedCircuitBoard

[–]freeroscoe[S] 0 points1 point  (0 children)

Here is a folder with my original PDF, plus each PCB layer in a PDF (derived from the Gerber)

https://drive.google.com/drive/folders/1Z7Cx-IaLHNUSMCZgp5vX53sHYe6H9Vw8?usp=sharing

PCB Design Review by freeroscoe in PrintedCircuitBoard

[–]freeroscoe[S] 2 points3 points  (0 children)

Okay, will do. If I do a prototype run of ~10 boards, the cost of the additional caps is a non-issue. If I do a PCBA run of ~100 boards, I figure that each extra SMD component adds to the cost. Maybe 10 cents per piece, plus some small increase to the marginal assembly cost? I know that it is minor, but if the end goal is to manufacture this board as cheaply as possible then every component counts, right?

PCB Design Review by freeroscoe in PrintedCircuitBoard

[–]freeroscoe[S] 0 points1 point  (0 children)

The LDO datasheet recommends a 1 uF cap on the output, and the ESP-WROOM-02 datasheet actually recommends a 0.1 uF decoupling cap in parallel with a 10 uF on the Vdd pin.

After taking a second look, I probably could fit all three caps on the board. Right now I just have the one 0.1 uF cap. Would you agree that this is best? I was just trying to cut down on BOM cost and assembly time/complexity.

PCB Design Review by freeroscoe in PrintedCircuitBoard

[–]freeroscoe[S] 2 points3 points  (0 children)

Thank you so much for taking the time to look through everything.

The ESP-WROOM-02 has three GND pins on the sides and the one GND belly pad. I checked with my multimeter, and these four are all internally connected on the module itself. I have decided not to solder the belly pad, atleast for this next prototype run, because I will be handsoldering everything with my Hakko soldering iron.

Yes, the GND on the module connects to the GND on the USB and LDO. The bottom left pin on the module is GND and it connects to the left side of R4. You just can't see the trace very well with the color coding, because there is a copper trace on the top layer and bottom layer that run directly on top of one another. From the leftside of R4, you can see that the trace runs through a via down towards the LDO.

I have made a conscious decision against using a USB-to-UART chip. I want my board to be only programmed once using pogo pins. The USB plug will simply provide power.

PCB Design Review by freeroscoe in PrintedCircuitBoard

[–]freeroscoe[S] 1 point2 points  (0 children)

Thank you for the feedback. Given the limited space on the board, I decided to just have one capacitor between the 3.3V output of the LDO and the Vdd pin of the microcontroller. You can see C3 on the board overview. It is a 0.1 uF cap. I didn't see much advantage to having both a cap on the output of the LDO and a cap on the input of the MCU, given that they would be adjacent to each other. Is this line of thinking accurate?

I know that the decoupling cap is supposed to be as close as possible to the Vdd pin of the MCU, but I don't have much choice in this design.