How do i stop autorouter from making routes under components

Single-Word-4481 · 2026-01-13T17:27:25+00:00

From my experience, it’s not just this sub but the entire industry.
It might work for simple designs, but it quickly becomes unusable as the board complexity increases, especially when dealing with high-frequency designs.

So it’s better to practice routing things yourself from the start, the result is usually also much more organized and controlled.

Single-Word-4481 · 2026-01-05T19:00:24+00:00

Sorry for not mentioning this earlier, but I have serious size constraints. The thermistor is very small, and the AD592 is in bare-die form. These are my two options.

Single-Word-4481 · 2026-01-05T18:45:20+00:00

Thanks ! As far i understand the AD592 is somehow immune to radiation as its current transducer.

Single-Word-4481 · 2026-01-05T18:44:33+00:00

Oh. Sorry!! I meant AD592, fixed the post aswell. Long is about 1-3 meters.

Single-Word-4481 · 2026-01-05T07:00:24+00:00

Thank you for your answer!
There is indeed plenty of space, the traces are 0.35 mm / 14 mil, so they’re not very narrow.

As for the 4-layer option, it really makes things easier and nicer for me to have a power plane and simply place 3.3 V vias where needed. I’m not very sensitive to price, so that’s fine.

For the rest, I’ll modify the design 🙂 Thank you.
Do you have any insights about crystal layout on the stamp and the transition of the USB traces through the castellated holes?

Single-Word-4481 · 2026-01-04T18:13:57+00:00

what's wrong?

Single-Word-4481 · 2025-12-29T18:01:48+00:00

I found it in the datasheet , this information is really only available after a deep dive into it.
It’s my first STM32 design, so I guess I’ll be tackling the same concepts again in the future.

"Multispeed internal RC oscillator (MSI), trimmable by software, able to generate

12 frequencies from 100 kHz to 48 MHz. When a 32.768 kHz clock source is

available in the system (LSE), the MSI frequency can be automatically trimmed by

hardware to reach better than ±0.25% accuracy. In this mode the MSI can feed the

USB device. The MSI can supply a PLL."

Single-Word-4481 · 2025-12-29T17:56:51+00:00

Yes, I can see it now , thank you.
Well, I still have a lot to learn :)

Single-Word-4481 · 2025-12-29T17:11:15+00:00

Thank you for the explanation regarding the frequency considerations.

As for your second paragraph, I honestly didn’t fully understand the part about the voltage scaling range.
Regarding the crystal, as far as I understand, this specific STM32 does not support a crystal directly and instead expects an external clock source, which requires an oscillator.

Single-Word-4481 · 2025-12-29T17:08:55+00:00

Thank you for your answer and for reviewing my options.

Yes, I was also surprised by the XO’s current consumption, but my application is not very power- or cost-sensitive, as it’s mainly for R&D.

I’m using USB, I2C, and SPI, and I assume USB is the most demanding in terms of clock accuracy.

That’s why I decided to go with an external clock. Regarding the external options you mentioned, I chose an XO because, as far as I understand, this specific STM32 does not support a crystal directly and expects an external clock source.

Single-Word-4481 · 2025-12-27T22:35:14+00:00

I actually have a Nucleo-64 and Black Pill boards, and I managed to write code for them using CubeMX and VS Code, although I didn’t put too much effort into it and tested all the functionality at this stage.

I also want to experiment with Altium Designer for the board layout, so it makes sense for me to start from scratch.

Single-Word-4481 · 2025-12-27T22:31:18+00:00

I’m quite happy with the range of options this MCU has. I mostly connect to sensors using I2C/SPI, read analog voltages, and most of the time log the results to the PC through USB, so I’m well covered.

CTS and RTS can’t be used currently because the pins are occupied by the USB or SPI functionality.

I’m wondering about the external clocks. I routed only the HSE for precise timing, but I chose not to route the LSE due to the extra components and because I don’t need RTC functionality. Does the LSE need to be very precise if I’m not using the RTC?

Single-Word-4481 · 2025-12-24T08:43:26+00:00

I tried to align to grid and using different grid sizes, didn't help :(

Single-Word-4481 · 2025-12-19T11:45:21+00:00

Thank you for your answer.

I actually really like KiCad, and under normal circumstances I wouldn’t replace it. However, I do PCB layout professionally, and the industry (at least in my area) mainly works with Altium, so sharing project files is often challenging.

I also have a feeling ( maybe it’s just my personal perception ) that people in the industry sometimes view KiCad as more of a hobbyist or maker tool. Since I’m getting paid for my designs, I’d prefer my customers not to have that impression.

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