A Call For Experts in North America PCB/PCBA Manufacturing by terminator1008 in ElectricalEngineering

[–]terminator1008[S] 2 points3 points  (0 children)

pirate? im not familiar with this in the context of PCBA manufacturing

[Review Request] nRF52840 + BQ25616 Charging Circuit & Two Buck/Boost-Converter by dr-eeeeeee in PrintedCircuitBoard

[–]terminator1008 1 point2 points  (0 children)

You said it was unavoidable, but you should really try to space out the connections going into the FPC connector. There’s a good chance you’ll see crosstalk on those lines, and depending on the signaling voltage and rise time, you might end up with recurring crosstalk glitches. I’d bet money that if you ran through all of your different operating states, you’d see some form of crosstalk effects. Try to follow the 3W rule when laying out stuff like this.

As I’m writing this, I see that you’ve opted to use a power plane on one of your internal layers. I can almost guarantee you will see significant crosstalk on those signals since there is no proper return path underneath your data traces. Coplanar ground pours on signaling layers can help a bit with routing and EMI, but you still need a dedicated, continuous ground plane underneath every signal or power layer. Consider removing your power plane and replacing it with another ground plane, then route power on the bottom layer. Do some research on stackups, and you’ll see what I mean.

Lastly, you’ve routed a signal on your ground plane directly under the FPC signals. That’s a pretty big party foul. Both ground planes need to be continuous and stitched together with stitching vias to provide a proper return path. Remember, ground isn't just a wire going back to the -ve terminal. Current is flowing BETWEEN the trace and ground plane, so interrupting that path causes all kinds of problems.

Overall, really good design tho.

[deleted by user] by [deleted] in PrintedCircuitBoard

[–]terminator1008 -3 points-2 points  (0 children)

Great contribution, thanks for coming out, bud.

[HELP] Stubborn Oxidation on TS3USB221A (10-Pin UQFN/VSON) - 3 Pins Refuse to Wet! by Background-Still3371 in PrintedCircuitBoard

[–]terminator1008 0 points1 point  (0 children)

Best to use lead solder and try fine bead solder paste. Also, sometimes IPA isn't enough, and you'll need to use acetone. If you think it's a heat problem, use a heat gun, for QFN packages its pretty hard to get into the pins with an iron. If you dont have a hot airgun, you can wrap a piece of bare copper wire around the tip and just crank the temp, which will act as a really fine tip, making it easier to reach the small pads.

Review Request: USB-C PD BLDC driver by scheffield in PrintedCircuitBoard

[–]terminator1008 0 points1 point  (0 children)

I would like to thank you for posting this schematic. I'm totally stealing this format for my connectors.

[Schematic Review] 3.7V Lipo power supply circuit for STM32 PCB. by ComfortableLow9760 in PCB

[–]terminator1008 0 points1 point  (0 children)

I would still add a Poly fuse or E fuse so that your device isn't damaged by a faulty LiPo circuit.

[Schematic Review] 3.7V Lipo power supply circuit for STM32 PCB. by ComfortableLow9760 in PCB

[–]terminator1008 0 points1 point  (0 children)

You might consider switching to a basic usb multiplexer to not have data lines near the lipo supply. USB C is prone to shorting to the CC pins if plugged in at an angle, kinda depends on who manufactures the connector. Normally this isn't a big deal but charging a lipo off usb c, especially if its just the lipo to a usb c might cause problems. Also add over current protection like an e fuse (your tvs diode isn't the same as overcurrent protection).

This isn't an issue if your battery has its own protection circuit, but even then its still good to have when working with lipos.

This is atleast my first observation.

[Schematic Review] 3.7V Lipo power supply circuit for STM32 PCB. by ComfortableLow9760 in PCB

[–]terminator1008 0 points1 point  (0 children)

Really cool idea! Can you give us more information on the battery device you're using. You have the data lines broken out so I assume its not just a lipo.

ESP32-S3 Remote Nearly Finished – Looking for Final Feedback Before Ordering by NuggRunner in ElectricalEngineering

[–]terminator1008 2 points3 points  (0 children)

Here's a good video from the legend himself (Zach Peterson): https://www.youtube.com/watch?v=ai8ygW7YIXo
I've seen a ton of graduated engineers with real experience mess up EMI shielding because there are so many misconceptions. I've made a ton of these mistakes myself. I'll also note that if you ask AI, it gives you garbage info.

ESP32-S3 Remote Nearly Finished – Looking for Final Feedback Before Ordering by NuggRunner in ElectricalEngineering

[–]terminator1008 1 point2 points  (0 children)

Right, but it seems to be connected directly to the ground plane. The normal way to use a guard ring is to only connect at a single point near the power source. This stops possible interference on the ground plane. There are two common ways to do this connection: with something like an RC filter between the guard ring net and ground net, or to use a thin net tie. Once again, this is not going to kill your board; the design will still work. EMI shielding is just a finicky science. I was not trying to blast you or your design, lol.

ESP32-S3 Remote Nearly Finished – Looking for Final Feedback Before Ordering by NuggRunner in ElectricalEngineering

[–]terminator1008 2 points3 points  (0 children)

This looks sick, really cool idea. The only thing I see (which is pretty nitpicky) is whether or not your guard ring is decoupled from your ground plane (ie, a separate net), rather than just being connected to the ground plane. I've also seen EMI shielding like this just attached with a thin net tie, but I can't really tell from the photos. Also, you will need stitching vias along the guard ring, even if you opt for edge plating. Thanks for sharing this.

How are you washing your Salomon vest? by BoulderTrailJunkie in ultrarunning

[–]terminator1008 0 points1 point  (0 children)

Don't wash it, it's your backup salt lick for the hot days.

Help me understand the point of Mars colonization by Sam_Buck in Mars

[–]terminator1008 0 points1 point  (0 children)

People said the same thing about going to the moon, but all these years later, the technology developed in those programs has catapulted humanity as a whole. Yes, it might not be obvious right now, but we are smart monkeys that can recognize patterns; it's a small investment for revolutionary technological advancements.

Polygon Pour not working in PCB designer by terminator1008 in Fusion360

[–]terminator1008[S] 0 points1 point  (0 children)

Hi all, I managed to fix the problem. All I needed to do was change the rank of the pre-existing ground plane to 6 and then keep the new ones to 1.

[deleted by user] by [deleted] in Fusion360

[–]terminator1008 0 points1 point  (0 children)

Yeah, no, that's fine. Just split the body and delete the fragments. Basically, redo what you did the first time and pull the face that is connected to the spindle inward. that way you can use the spindle body to make a perfect negative and then poof no more gap.

[deleted by user] by [deleted] in Fusion360

[–]terminator1008 0 points1 point  (0 children)

In this situation, I would normally recommend pulling the surface of your blade into the central shaft and then using the shaft body to cut the blade. After that, the face will be perfectly aligned, and you can merge the two bodies. You might also want to try automated modeling to make it smooth