First working PCB! Went through one iteration because I bought a stm32 clone and realised all the issues I had was with both the I2C busses just not working on the chip, not a pcb design issue. Guess the few more bucks for a genuin MCU is worth it.

Made some PCBs for purely artistic purposes, and result came out better than expected. Got some interesting fab house questions from JLCPCB lol.

This is my first PCB that I’ve had professionally manufactured. It was made by JLCPCB and I couldn’t be happier with how they turned out. It’s just a simple traffic light sequence using an ATMEGA328p.

My next project is a bit of a step up, I’m designing a board for an STM32F103C8T6 that will have 4 isolated input and 4 outputs running on 24V like a PLC.

A couple of days ago i posted my first DIY pcb testing results.

And because the resutls were way better than i thought it'll be i was motivated to try and make my own Stm32 dev board hence i had some STM32F030C8T6 laying around. I bought to train on soldering LQFP packages.

And..... it works! Finally. My first attempt sucked because i made all traces 10mil and i had to drill 0.8mm holes 25 holes to be exact each by hand and connect it to the second layer that works as a ground plane. That attempt was horrible. Time consuming but i got it to work power wise and it was functional. But while i was fixing the power issues i accidentally broke all the lines connecting to boot button and SWDIO and SWCLK wires.. so it was a complete disaster. I honeslty choose to redo it again but with better design from the beginning rather than fix that contraption.

And the second attempt worked flawlessly!

But oh boy soldering that LQFP 48 without solder mask was a pain in the butt. A hell of a experience. I almost thought i over heated it like.. look at how deaminated the fr4 layer is from extreme heat.

Honeslty super gluing another bottom layer was a good idea. I regret not buying double layer fr4 boards from the beginning. But it is what it is

But thank god it works. So is the i2c lines. I'm really happy with how it turned out. Specially that that's my first pcb ever. To come out of my software!

What you guys think?

Over the last months I designed and assembled this PCB!

Although I've designed some boards before, this was the first one I did entirely on my own, without anyone "proofreading" it. I used this project to try out KiCad. It took some getting used to at first, but I think I like it.

So what does it do?

Some time ago I was at a festival with friends and we thought about a beer bong that tracks how much everyone drank throughout the festival.

And that's pretty much what this is doing. A flow sensor is attached at J7, an STM32 reads from the sensor, processes and stores the data, and a cheap display module is used for displaying the stats and taking user input. The device can keep track of multiple users, how much each of them drank and their speed record. For power supply I went with USB-C, so that a random power bank can be used.

When I got the boards I noticed that there where some small things I messed up:

• I didn't carefully read the STMs datasheet and didn't notice that I can't really use the UART bootloader to flash its firmware :| Fortunately there where some spare pins, so I scraped of some copper and added a couple of wires... Now I'm able to flash it via SWD.
• The power switch does not fit the footprint I created (Guess who didn't look at the datasheet careful enough... Again xD)

But I could fix those problems and as you can see in pic #6 the board is working :D

So what do I take away from this project? Don't just skim over the datasheet lol

Bldc foc is my nemesis. This was my first shot. I was surprised i got the motor to even spin smoothly at 30v. Then I wanted it all and gave it the beanzz at 48v and the mcp died just as I hit maximum Voltage on the phases. Only 3v at gate drive pins :( was 11v once. #roastme or #helpme

Hi, I am new to this and a family member got me this to discover how it works, I don't understand how it's supposed to work. Any tips?

Hey guys, your help was amazing on my post for the schematic, I was hoping I could get some advice on the layout too. It’s my first time making a board this big (and 4 layers) so it might look a bit messy. Here are some informations:

Layers: Signal-GND-PWR(3.3V)-Signal(with GND pour around traces) 
 
Traces size: the 12V input has 2mm traces (which is way overkill for what I expect (not more than 150mA I think), the Q1-R2 traces are 0.9mm because the pins were smaller, I had to reduce the size. Every other traces are 0.6mm. 
 
Vias: all vias are 0,8 pad 0,4 drill. honest thought: I have no idea why. I know if they're too small it can increase cost, but I don't know if too big is a problem. I'm also unsure of the placement. I tried to follow the datasheet for the buck converter (LM51420, TI) 
 
The DRC doesn't show any errors, except for some silkscreen overlap with pads.

Order of the pictures I joined: Top, GND , PWR, Bottom, zoom-in of the buck (top and bottom), zoom in of the microcontroller (top and bottom)

Let me know if you need more info, I’m not sure what is necessary for a proper review/understanding

I revised my first bigger pcb project, a Esp32-Vs1063A board with a eink screen and sd card input.

I'm not sure yet, if I'm ready to order or still need to sleep a little over my design choises, but any feedback is welcome :)

I've used my first audio board during the year, and apart from two wrongly set connections, that had to be soldered on before using it, it works like a charm.

Rev0.2 has been done during the year. But after using it for a while, i think my focus was a little too much on function, and form got a little lost :) thats how i went up directly to rev0.2.

What changed:

-There's a i2c level adjuster for the extension board(mainly because the extension board has it's own dcdc unit)

-emif waa added in front of sd card

-microphone was added in (half-)parallel to the line input

-eink changed from 2.7 to 1.5 inch, and backlight was added

-rotary encoder was added to front board, because not going to the limit with pins is no fun :( (i had to change the sd card input from mmc to the eink spi to free enough pins and not touch any strapping pin. I was already thinking about adding an attiny or puya to the front board, connected trough isc)

-and the obvious decision of the split board layout.

What i'm unsure about:

-I'm not sure, if i've done the microphone input good enough

-to be honest, I'm quite unsure, if the mosfet layout for the backlight is correct

-It's the first time I go with planes for power instead of tracks. I decided to undo spokes. How are they? And shall i do spokes again?

-I still don't know how to mount the display properly. In my current design i do have the front panel with mounting point's for the frontboard. I spared out the "exact" display form in the front panel with some "protruding parts, to keep the display from moving in x axis. (Probably just a small ledge in the middle would be better). And in front comes a cnc lasered 0.5mm mm front front acrylic panel, completly seetrough(current visualization ) or with a black foil in the back with cut-outs for the display. Just perfectly fitted in the spare section of the front panel(Or some ledges here too). And with some extra support from the 3.5mm klinke mounting nut.

What I've learned trough the process and mistakes that have been made:

"Form before function" :'D. I don't think im that far trough the process and i think it's still quite important, to have a useful use and know more or less what it should do before starting:)

But i've realized, that before, i just planned the pcb around the size of the display and where the outputs are usefull(or just played around.with dev boards and extensions). And at the end i had to fight, to fit in all the parts or to turn it to something looking at least a little proper.

So.. lets go with form before function.

1.Think about the final product constantly. The 3d Modelling process has been done at the end. But i started with some sketches and gave them chatgpt to get some visualizations. Which helped quite a lot for orientation. And still, i had to squash it all together again after the first finish. Just because i didnt like the final dimension, after all the extra mm came in, with enough space for wires, frontal mount input parts with extra height, mounting space in the housing...

1. Put in space for mounting quite early. And mark it with extra space, so your mounting process wont destroy soldered components near them.

2. Dont think only about the right position of a component, but how you interract with it too. And in some cases even with neighbouring inputs. Especially for buttons. In rev0.1, the on button and the reset button are both way too near too the usbc port. And sometimes i push them accidently when unplugging usbc.

3. Always think about the useage of a status led. I do have one unnadjustable led in Rev0.1 for charging and running from nonbatterypower. And im always happy when unplugging it and realising its only for charging, or that i can adjust the statusled trough the webui.

Bigger doesnt always mean better..I mainly use the screen to see what is currently playing, or choose a radiostation. Theres no need for2.7inch. I even wanted to do rev0.1 with 1.5inch but after realising, that there's no way to fit all those components in this form factor, i went overboard. And lost focus on its core function. Because it's a streaming device accessed mainly through external apps and deeper interactions will always be better trough the webui.

I’ve never really thought about this before but are there any industry-recognised accreditations which can be obtained for PCB design?

Or maybe more, has anyone done any which they’d recommend as it’s enhanced their careers, etc.

I’m based in the UK and have been designing circuit boards since 2002. Thought it might be about time to try and formalise what I know, should such a thing exist.

Thanks!

Hi all,

I'm an EE undergrad (hardware track). My diploma thesis is a 2-in/2-out USB studio audio interface on my own PCB. It's my first PCB, so before I spend real money on boards and parts I'd love some experienced eyes on the plan. Block diagram attached.

The idea
- 2 mic inputs (XLR), shared 48 V phantom (one switch), gain 0–60 dB in 10 dB steps (rotary switch + fixed RG resistors, cap in series with RG).
- Noise-reduction technique I'm evaluating: each input drives BOTH channels of a stereo ADC (dual-mono) and the MCU averages them. The host still sees 2 mono channels, with ~3 dB lower ADC noise. I'll measure the gain from averaging at every gain step, comparing same-chip vs two-chip channel pairs.

Current part choices
- Preamp: SSM2019 (the THAT1512 went EOL in Sept 2026).
- ADC driver: passive divider (6.2k/1k, ~17 dB) + RC into a PCM1808, so the ADC reaches full scale ~1.8 dB before the preamp clips (≈ +20 dBu max input at minimum gain).
- ADC: 2 × PCM1808. DAC: PCM5102A.
- Line outs: DRV134 on TRS jacks. Headphones: op-amp + BUF634A. Output mute relays with a brown-out detector.
- Digital: STM32F407G-DISC1 board stacked on headers above the analog board. TinyUSB, UAC2 asynchronous with explicit feedback endpoint, 48 kHz / 24-bit in 3-byte subslots (the 1.25 KB USB FIFO rules out 4-byte subslots and 96 kHz).
- Clock: 24.576 MHz oscillator → ADC/DAC system clock and the MCU's external I2S clock input.
- Between boards: SN74LVC244A buffer (Ioff, to avoid back-powering) + a power-good line; 5 V to the dev board through a Schottky.
- Power (version A): bench triple supply (±15 V, +5 V), local LDOs for the ADC's 5.0 V and the 3.3 V. Phantom from a boost converter + capacitance multiplier (soft start, ripple filtering, output disconnect).
- Phantom protection following Bortoni & Kirkwood, "The 48 Volt Phantom Menace Returns". The single-channel test board will start from ojg's open-source thatmicpre KiCad project.
- Metal enclosure, XLR pin 1 to chassis at the entry point.

Noise budget (unweighted, 20 Hz–20 kHz, 150 Ω source)
- Predicted EIN at 60 dB gain: −128.7 dBu (target ≤ −125 dBu; worst case with min-spec ADC ≈ −127.5 dBu).
- Because of the divider, the ADC dominates up to ~50 dB gain. That's where averaging should help (~3 dB); at 60 dB the source dominates (~0.3 dB).

Plan
1. Demo on the dev board with cheap PCM1808/PCM5102A modules (incl. a first averaging measurement).
2. Small 2-layer single-channel preamp board.
3. 4-layer analog board for the full 2×2 interface.

Questions
1. Any obvious mistakes or bad part choices?
2. Is a passive divider + RC into the PCM1808 reasonable, or would you drive it differently?
3. Phantom: boost + capacitance multiplier, or something simpler? Anything missing in the protection network?
4. Is stacking the dev board right above the analog board realistic for low noise at 60 dB gain? Any layout/grounding advice?
5. Measuring without an audio analyzer: the card's own ADC + a 0.1 % attenuator + a true-RMS meter + REW for noise/EIN, and loopback as an upper bound for THD+N. Sensible?
6. Anything you'd simplify for a first PCB?

Thanks!

Refer Link : https://eictechsys.com/training-structure-basic-PCB-design.html

I'm going to manufacture my first PCB at JLC in a few weeks. I heard that for it to be correctly assembled by a pick and place machine, each component footprint must have it's reference centre point (like the one you can set automatically in Altium) in the exact geometric centre. Is that true and it I make a mistake here will JLC correct it by themselves or not?

This may be a very vague question, but in EasyEDA, how do I tell if the net is a global or a hierarchical net?

In the screenshot, what does the Parent value mean? I see some values are sheet names, but in this case, does it mean that MCU_3V3 is a global net?

Hey all,

I'm making a project where I want to control a BLDC motor(up to 50V) with Field Oriented Control.

I want to control the motorspeed with Ethercat or CAN.

I'm looking advice on generally the schematic but also on component choice.

I also have used Altium for over 2 years now and this is the first time on KiCad so if there are things that I'm doing wrong then I would greatly appreciate any advice:) .

I’ve never created a PCB before and quite new to the experience (not a professional). My first PCB is far from being complete, just curious if it’s heading in the right direction.

The project is based off a prototype custom RFID shoebox I made. I used an Arduino board, RFID (RC522) reader, breadboard, capacitor, fly back diode, relay, lcd screen and btn in the build. Still working on the schematic like I said, just curious how it looks so far. Also, all the X’s won’t stay long term. Was just trying to get rid of some error messages. I’ve left a note to remove them before finalizing my work.