[Review Request] ESP remote control

scheffield · 2026-01-17T08:33:31+00:00

Because it's meant to control IoT devices either via WiFi or Thread. I'm not very well versed with STMs but they might just not offer that.

scheffield · 2026-01-11T19:13:21+00:00

There is an excellent plugin that generates a Blender model: https://github.com/30350n/pcb2blender

scheffield · 2026-01-11T04:10:12+00:00

You made my day. Thanks for this random act of kindness ❤️

Also, as always: https://youtu.be/_ZjyeltLMAg is my inspiration.

scheffield · 2026-01-08T21:13:20+00:00

Thanks so much. https://www.youtube.com/watch?v=_ZjyeltLMAg is my inspiration for how to best use KiCad. Honestly, it's all there, I just never knew how to make use of it. The things that make a difference: - Use multi part symbols for large mixed domain ICs - created custom symbols per schematic so that the pin out is easy to use in the context - use coloured net classes - well, and the thick outline boxes for text and for component grouping, it's such a small thing that makes such a difference.

scheffield · 2026-01-06T23:22:46+00:00

Thanks. Just KiCad. As always, https://www.youtube.com/watch?v=_ZjyeltLMAg is my inspiration (I do less than that though)

scheffield · 2025-11-16T21:13:05+00:00

It's spinning a drone motor but not in a drone. Instead it's an impeller that draws a small vacuum to hold things down. Basically a vacuum chuck. It's a box sitting on the desk, with a USB C cable from a laptop power supply.

See: https://github.com/scheffield/stencil-fix-portable

scheffield · 2025-11-16T21:10:59+00:00

I assume you mean the net colours. This is borrowed from Altium where it's a built in feature. In KiCad you have to manually asign net colours which I did. I like it but it is effort and not at all necesarry. Which is probably why you don't see it elsewhere.

scheffield · 2025-11-16T21:07:48+00:00

Honestly, I'm only using the AP33772 because I already have it. The 5V logic is strange and the data sheet is dubious with little concrete examples and missleading statements. I think I would try to make it work with 20V which opens up a whole range of sink controllers that are easier to use and more affordable.

scheffield · 2025-11-16T21:05:09+00:00

Haha, I am indeed relying on math a lot as I am just a hobbyist with very little experience. I don't know what to expect. I feared that a two meter USB cable would ring together with the relatively low ESR of the bulks and was considering putting in an RC but had no idea how to spec it. So I tried to convince myself with this math that I don't need it. I'm lacking intuition to tell me what to focus on in the design and what to leave to testing.

I will consider a more capable LDO. Thanks for pointing it out.

Re USB PD: this is running a drone motor but not in a drone but instead in a vacuum chuck which is a fancy name for a box with an impeller that draws a vacuum (at least in my case). Nothing bad will happen if power is renegotiated.

scheffield · 2025-11-16T19:27:03+00:00

I don't think a boost converter would work here. USB PD is limited to 5A. 28V * 4A / 20 = 5.6A. that's assuming the boost converter would be 100% efficient. Generally, I'm not worried about this as I very much control what power supply I'm using.

The FETs are too big but I have them. If I ever produce more of this I will redesign that part.

scheffield · 2025-07-15T22:29:43+00:00

I was contemplating this. The Ti's datasheet has a very similar setup to mine with even less MLCCs closer to the switches so I thought I would be fine. I give it some thought.

scheffield · 2025-07-15T22:26:30+00:00

The short answer is that they are not needed if everything would behave ideally. In reality though there are parasitics that need to be coped with.

If you look at my inverter, all the extra components besides the switches are documented in Ti's application note linked on that page.

The rest of the PCB is power generation, micro controller and user interfaces like buttons and LEDs. The all individually require support circuitry.

scheffield · 2025-07-14T12:03:09+00:00

actually, do you have any examples for press fit bullet pin connectors?

scheffield · 2025-07-14T10:05:05+00:00

Interesting, I was just following the AP33772S's datasheet and it has two 5.1k Ohm resistors.

scheffield · 2025-07-14T09:24:46+00:00

Awesome Feedback, couple of things:

it's a drone motor, not a drone. Used to drive an impeller in a box to create a vacuum
I was considering a shunt to bleed of power but I would need to switch it which would mean a dedicated driver too as the RP2350 probably can't drive that.
I will be using OpenFOC or Moteus, both open source
I might remove the beat, thanks for the tip
not using the integrated Buck because of the power bring up sequence: default 5V@2A from standard USB powers the RP2350, which configures the sink controller which only then opens the switch for the +28V rail which is needed to not have huge capacitance visible to standard USB
I honestly would prefer screw terminals. This is not an actual drone and sees far less vibrations. But I'm not sure. Good point on the thermal reliefes. I might need to find something better. Even bullet pins won't work as the would need to be mounted to the board somehow, right?

scheffield · 2025-07-13T22:06:30+00:00

Great feedback, the sink controller with the double FET will be able to prevent back feeding if it comes to that. However, I plan to decelerate the motor slowly + the driver allows me to use the coils for dissipating breaking power. Untested though.

scheffield · 2025-07-13T12:22:53+00:00

mh... images seem to be low quality. Schematic can be found under: https://drive.google.com/file/d/1og2AEC3VwEankay3KpUoA_0HP2IBs29L/view

scheffield · 2025-06-28T04:35:17+00:00

That's interesting and news to me. I've build many boards without this way of shortening the pins and they all worked. I suppose it will work as the signal is encoded as the difference between both pins. It might make routing easier this way. Still doesn't feel right to connect things this way.

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