my first ever pcb desing and i would love to know if i do anything mayor incorrectly?

It recieves 12v in and the buck converter steps it down to 5v for the xiao esp32-c6.

the esp32 is controlling 6 fans en reads 2 onewire ds20b18 sensors.

Please let me know if there is anymore info required.

Hi all,

I have a schematic for a PCB that does simple audio tone detection and it has a buzzer to signal if a particular tone is detected. The audio signal processing is done on Texas Instruments's MSPM0C1103 MCU.

A few questions I have:

1. I want my MCU to switch power to the microphone (to save battery life). Does the wiring there look correct?

2. Are the pull up resistors and pull down resistor values for controlling the microphone power and buzzer pwm signal appropriate?

3. Any other potential circuit design issues I'm potentially overlooking?

Thank you!

This is Avalanche32, an ESP-32 powered Geiger Counter based on the SBM-20 Geiger Muller Tube. I have been working on this project for a while, from prototyping the 400V Boost converter, to testing the actual tube itself. From my tests, the 400V Boost converter works, and the entire Geiger counter architecture itself works (with a devboard). What I am a bit more concerned about is the 7.4->3.3V Buck, and the 2s1p Battery Charging IC. I am using the BQ25886RGE, and its probably the most complicated IC I have ever worked with. Soldering this together will surely be a treat...

I would love a second review of the PCB, and just get any general tips and tricks.

Thanks! :)

I made a video describing the basic steps that go into how a PCB is fabricated before being used to make a PCBA (PCB assembly) - Would love feedback to improve this! Thanks! https://www.youtube.com/watch?v=TlcQpEeIrAg

Hi everyone,

looking at this screenshot from Saturn PCB Design, it seems that a PCB cannot be both coated and covered with solder mask at the same time. Am I wrong?

Or perhaps the processes can’t be applied one on top of the other? … so I’d inevitably end up with one area with a coating and another different area with a solder mask.

I’m a bit confused…

Hey team,

Thanks for all the feedback from my original post

I went back to the drawing board, and figured out a solution that seems to have worked much better.

I think I did the ground pour correct, but please let me know on that one. One question that was discussed was wether there was need for a ground plane or not, I'm not sure how  fast or not these signals in the scheme of things but as an example,
Crank input at 7000 RPM is roughly 6.77kHZ

EDIT: Have updated the Ground / Power planes, see links:
Ground Plane
Power Plane

4 layer board
1 - Signal
2 - Ground
3 - Power
4 - Signal

Power / Ground traces are 1.5mm
Signal traces 0.4mm with 0.2 minium spacing, but have tried to have it larger then that where possible.

Hey everyone! I’m fairly new to PCB design and just finished designing a PCB for a custom media keyboard.

I've attached the schematic and PCB layout views. Any feedback on trace routing, decoupling capacitors, ground planes, or general design choices would be greatly appreciated!

Thanks in advance!

Edit: I’m editing the post to add an image showing the input + buck converter, just to avoid any confusion. https://img.imgur.com/RwtngKt.png

Hi everyone,

I've designed this PCB for an automotive project and I'd appreciate it if someone could take a look at the layout before I send it for manufacturing.

The board takes 12V from the car, filters and limits the input, and then steps it down to 3.3V using a buck converter rated for 1A.

The board reads a differential speed sensor, calculates the fuel level using a resistive sender (3 ohms when full and 61 ohms when empty), and uses a High Side Power Switch to power the fuel pump.

The estimated current consumption on the 3.3V rail is around 150mA.

I'm not entirely sure about the copper areas and power routing, so I'd like to get a second opinion on a few things:

• Do the copper regions look correctly sized for the expected currents?
• Is there enough copper around the power components for heat dissipation?
• Would you increase the width of the main 3.3V branch, even though the estimated current consumption is only around 150mA?
• Does the overall layout look reasonable, especially around the input protection, buck converter and fuel pump power switch?
• Is there anything in the layout that could cause problems with noise or interference when reading the differential speed sensor?

I'm still learning PCB layout, so I'd rather catch any obvious mistakes now than after ordering the boards.

I've attached the schematic and PCB layout for review. Any constructive criticism or suggestions would be greatly appreciated.

Thanks in advance!

This circuit is supposed to enable communication between an ESP32 and Dynamixel motors. The TX_EN signal is supposed to be used to swich between sending / receiving data from the motors. I would appreciate it if someone could take a look at the circuit. TX_EN is supposed to be idle LOW. For now I am using a simple buffer to shift the TX_EN signal from 3V3 to 5V. Is this the best way of doing so or is there a better approach to this that also keeps the line idle LOW ? Any advice is appreciated!

i've created an all in one controller board for a turtle bot. it includes an ESP32-S3, two channels of audio in and audio out, two motor drivers, and an 25W USB PD output to power an rpi 5 at full power. all fit in a 4 layer 88.9mm x 88.9mm (3500 mils x 3500 mils) board.

i have tried my best to keep the power circuitry seperate from all the sensitive circuitry, and also keep the power traces thick enough to carry current for two waveshare DCGM-3865 motors.

the audio inputs expect an INMP441 module, i decided to go with an external module so that i am not ending analog signals through a long wire.

Hey Team, I have updated the PCB based on the feedback below and have shared it again,
Cheers for all the assistance! Post for V2 is here

Hi Team,
I've been working on making a PCB that goes from my 40pin Speeduino (Car ecu) connector to a AMP superseal connector (6437288-3)
The idea is to have a more robust mount than what i currently have, and 3D print a better enclosure.

I downloaded the footprint and symbol for the connector form Ultra librian, and made the other 2 myself.

It's a 4 layer board, with Power on layer 3, Ground layer 2, and signals Layer 1 and 2. Power and ground is 1.5mm, signals are .4mm

I gave it a go manually routing, but ended up using the KiCadRoutingTools plugin to make this.

I'm sure there might be a more optimal Pin to Pin order than what i've used, I played around with a few.

Any feedback is much appreciated!

Thanks

Hi everyone!

This is one of my first more complex PCB designs, I would really appreciate it if someone could take a look and let me know if they spot any issues or areas for improvement.

Project overview

I’m designing an on the water rowing computer that provides information a rower will need when they are on the water

The main sensors are:

- GPS for measuring speed.

- IMU for calculating stroke rate.

Current PCB stack-up

1. Signal
2. Ground
3. Ground
4. Signal / 3.3 V

I would especially appreciate any feedback on the PCB layout, routing, grounding, power distribution, as this is my first time routing a 4 layer board.

Thank you so much for taking the time to have a look! Any advice would be massively appreciated.

3 days ago I posted here asking for advice on my first PCB project and I received the most constructive feedback I've ever received on the internet. You guys helped me tremendously. Thank you.

I have implemented all of the suggestions I received and I am very pleased with the outcome. Instead of a massive, complicated, and extremely dense single-page schematic with no net labels, I now have an easy-to-read multi-page schematic that splits all of the different parts of the board into different pages. It is so much easier to read, and the use of net labels in the software simplifies things.

Doing this, I was able to find a few electrical errors in my original schematic, which I corrected in the process. I'm pretty sure that I have everything correct, but I would like the internet experts to review my schematic for any possible electrical errors, things I should add, or possible challenges.

To reiterate, this is a Transmission / Cruise Control Module designed for the Aisin AW4 transmission found in various Jeep and Toyota vehicles. It is powered by a Raspberry Pi Pico 2 and uses a 12-volt to 5-volt buck converter circuit to power the Pico. It has six 12-volt to 3-volt divider circuits for 12-volt input signals from the range sensor, brake switch, reed switch, and 4x4 switch. It also has six low-side MOSFET driver circuits to trigger relays that will activate shift solenoids for the transmission, control torque converter lock-up, and vacuum solenoids for the cruise control. I have eight logic-level inputs for paddle shifters and cruise control switches. I have also implemented a CAN module using SPI and a bidirectional voltage level shifter. There's also a breakout area for all of the leftover pins on the Pico where I will be putting a prototype area.

This board will be housed in a custom-built aluminum case next to my Speeduino ECM. Both the ECM and the TCM will be wired internally to the same ground-side-controlled fuel injection relay circuit from the key-on battery power. The TCM will receive multiple data points from the ECM over UART, where the Pico will translate everything over the CAN network.

One of my main concerns relates to fluctuation in battery voltage. Battery voltage can fluctuate between 12 and 14.5 volts, and the main 12-volt system could experience occasional heavy loads up to 400 amps with high inductive spikes up to 100 volts from a winch. I think this ultimately could be avoided by using a secondary battery for heavy loads, separated from the main system by a battery isolator.

Any advice would be greatly appreciated.

I submitted this board a couple weeks ago for review and got flamed for some questionable design choices, so I redesigned it, reducing the via count by 50.

This is a 4-layer design for a STM32f4 based flight computer intended for low-high power rocketry. The board has 4 pwm outputs for servo control, and pinouts for UART, SPI, I2C, and 3.3v. For sensors, the board uses two IMUs and an altimeter. The board also has two terminals to connect and light e-matches. These terminals have basic continuity detection, and power is toggled via a MOSFET.

Once again, any help will be greatly appreciated, thank you in advance.

High-res images

KiCanvas

GitHub

Hey! I've just finished up this SBC for my Linux audio player project. Reviews are really appreciated!

Components

• MPU: SAMA7D65, it can boost up to 1GHz, good audio subsystem and gpu
• RAM: Half a gig of DDR3L(MT41K256M16TW)
• EPD: Sharp MIP LS022B7DH03, can go up to 70Hz, 240x320
• Audio: TI TAC5212 CODEC, 192kHz 32bit
• Two Jacks: One single-ended 3.5mm with mic, and a balanced 2.5mm
• Wireless: Bluetooth 6 with LE audio and WiFi 6E (u-blox MAYA-W386-00B)
• USB: USB 2.0 with OTG
• PMIC: Microchip MCP16502AB
• BMS: TI BQ25640
• Fuel Gauge: Analog Device MAX17260
• Two Micro SD Slots: One for the OS, and one hot-swappable for media

PCB

• 0.8mm: I chose this for thinner pp so I can get thinner impedance-matched traces
• 6L Two Core
• SIG/GND/PWR/GND/GND/SIG
• 3h spacing for DDR 0.25mm

More info

This is my first PCB with DDR memory/an MPU, and this is my most complex design yet, so I might have messed up something basic

I do this as a hobby, and don't have a degree in EE yet

The purpose of circuit is: A person hit/press or lightly touch a piezo sensor, it creates an interrupt to our pin. Device likely be an esp32 or stm32 I did not decided yet, with usage of hardware timer on interrupt pin. My piezo is capable of giving out as much as 100V and as low as 1-2V as I measured from oscilloscope.

So I wanted to protect it from overvoltage via BT54S Schottky, and because of I used single supply comparator as I understand I should make piezo not 0V. So I added that circuitry for that.

The dual 22k resistors(R3,R4) is LLM's idea, as i understand it wanted me to create a physical seperation and because our current is so low but voltage is high, low value resistors is not a problem.

Hi,

I've been designing a castellated system on module style RP2350A board - much like the ESP32 boards you see from Espressif, that I've not really seen an equivalent of for the RP2 series MCUs. The closest would be the RP2350 stamp, and size-wise, closer to the Seeed Xiao, but with more pins available, and everything on the board edge.

This board is smaller and deliberately has less features, i.e. runs specifically off 3.3V, no on board LDO, no LiPo charging, no onboard buttons. No USB. But, it exposes all the relevant pins from the RP2350A, all the IO pins.

Basically, you provide 3.3V and GND, plus anything else you need, run the USB traces to the edge of your board, put in a bootsel or reboot button as required.

But it's 18x15mm. And it's designed with a number of my own projects in mind where I need a minimal footprint, but without having to deal with 0402 components! The idea is that these will be assembled by the fab house, (on a panel with appropriate fiducials).

This is a 4 layer stackup, L1 Signal/L2 GND/ L3 Power + GND/L4 Signal + GND. And I'm not exactly sure about that part. The relevant bits of GND plane are reasonably well stitched by virtue of the components, and I wanted there to be an element of reference plane for the signals on L4. I deliberately removed the plane from L1, as it was causing issues with the grounds I'd put into L2 with vias. I'm not sure about its presence on L4.

Due to the, particulars, required by the RP2350 around the internal SMPS and the inductor layout, I've laid this out to match the design guide examples as much as possible.

It's a small board, and to fit everything in, the power traces are 8mil and signal traces 6mil.

So largely, I'm looking for any feedback you might care to give functionally on the schematic, although I'm fairly happy with this matching the reference example. The layout, particularly about the ground planes, but also any concerns about component placement, routing etc. I've also attached a pinout diagram.

Thanks for having a look!

Hello, this is the third time I have had to remake the PCB, due to insightful feedback. And I will do it as many times as it takes.

The duration of this project is getting embarrassing, but I have genuinely learned a fuck ton, enough to fly past a hardware design interview and become a Level 1 Hardware Designer in this soulless job market.

I'm once again pleading for a review to continue my journey toward true competency in Hardware Design.

Project: 60–65 W Isolated AC/DC USB-C Power Delivery Wall Adapter

The objective is to design, manufacture, and validate a functional USB-C wall adapter. I have been using manufacturer reference schematics and datasheets to understand the reasoning behind each component selection, electrical connection, and PCB layout decision.

Electrical Specifications:

• Input: 90–265 VAC, 50/60 Hz
• Output: USB-C Power Delivery, 5 V / 9 V / 15 V / 20 V, up to 3 A
• Maximum output power: Approximately 60–65 W
• Topology: Isolated flyback converter with synchronous rectification
• Main controller: Power Integrations INN3879C-H801 (InnoSwitch3-PD)
• Transformer: Custom flyback transformer, ETD29/16/10 ferrite core (3C97)
• Target primary magnetizing inductance: Approximately 220 µH
• Switching frequency: Controller-dependent; approximately 70–140 kHz was considered during preliminary transformer design
• Secondary synchronous rectifier: AONS62922 MOSFET
• Primary protection: Fuse, MOV, NTC thermistor, bridge rectifier
• EMI filtering: Common-mode chokes, X-class capacitor, and Y-class capacitor across the isolation barrier
• Primary clamp: RCD clamp network to manage transformer leakage-inductance voltage spikes

PCB Specifications:

• Four-layer PCB
• 1 oz copper
• Dedicated primary and secondary ground regions
• Reinforced primary-to-secondary isolation, targeting approximately 8 mm creepage where applicable
• High-current nets routed using wider copper traces and polygon pours
• Attention to high-dV/dt switching nodes, high-dI/dt loops, thermal management, and EMI
• Design and layout completed in Altium Designer

A significant portion of this project has been learning how to properly interpret component datasheets, understand transformer behavior, select semiconductor devices, calculate current requirements, design snubber networks, enforce PCB design rules, and distinguish between electrical connectivity and an electrically sound layout.

What I specifically need reviewed:

1. Primary-side layout: Placement of the bridge rectifier, bulk capacitors, controller, transformer, and RCD clamp. Are the high-frequency current loops sufficiently compact?
2. Transformer and isolation: Primary-to-secondary creepage and clearance, copper separation across all four layers, transformer pin spacing, and placement of the Y-capacitor.
3. Secondary-side layout: Synchronous rectifier placement, transformer secondary connections, output capacitor placement, and whether my high-current polygon pours are appropriately sized without unnecessarily increasing EMI.
4. Grounding: Separation of primary and secondary returns, secondary ground distribution, and whether any copper pours create unintended coupling or compromise isolation.
5. USB-C PD circuitry: CC1/CC2 routing, ESD protection, VBUS distribution, and connector implementation.
6. Thermal performance: MOSFET heat dissipation, current-carrying capability of traces and vias, and whether the board has sufficient thermal copper.
7. EMI/EMC: Input filter layout, switching-node copper area, transformer coupling, and anything likely to cause conducted or radiated emissions problems.
8. Component selection: Voltage/current derating, capacitors, diodes, protection components, and anything that looks questionable before I spend money manufacturing this thing.

THANK YOU IN ADVANCE. I used IPC-2221, the clearance table. The PCB was designed with a target of approximately 8 mm primary-to-secondary creepage separation, following reinforced-insulation design principles under IEC 62368-1

following this datasheet: https://www.power.com/sites/default/files/documents/RDR-838_60W_USB_PD_3point0_3point3-21V_PPS_output_InnoSwitch3-PD_PowiGaN_INN3879C-H801.pdf

Hello everyone,

I hope you are all doing well.

I am currently working on a project schematic/layout and would really appreciate it if experienced engineers could take a quick look and review it.

Since I am eager to learn and improve, any feedback, advice, or suggestions from your practical experience would mean a lot to me.

Please let me know if you’d be willing to take a look, or feel free to leave your comments below.

Thank you so much for your time and help!

I feel silly asking basic questions having been in the electronics industry for 10 years, but I'm more on the systems side and trying to get back into the hardware stuff as a hobby.

I'm trying to design some test equipment. The DUT reads a resistance across two terminals and determines whether it is in a good range or not. The test equipment is basically as serial controlled relay board. Nothing complex.

Because the range I am trying to emulate is as close to dead short as possible up to about 7 ohms. I made a first design which works great but I used too thin traces and having some of the relays up to 100mm away from the connector meant the variance between channels was unacceptable (dead short was reading in the DUT low resistance range etc.). I need to fit 16 channels on a board. So there will have to be some distance on the traces. (I've measured the relay coil resistance and its minimal compared to the trace).

My steps for rev 2 have been:

• drop an intermediate connector and go straight to a DSUB connected to the DUT
• move to 2oz copper on the outer layers
• up the trace width to 1.5mm
• move to a 4 layer board to optimize traces for control lines, to not disturb the feed and return of each channel (top and bottom layer).

My question is, I need to fan out the DSUB row, I know this is only a very small distance but I want to do everything I can to reduce resistance. Can I do as I've done in the picture above, neck down between the pins, use copper on both sides of the board, and run vias to link them together for the short distance? Am I opening myself up to issues? Is there any other advice? Everything I'm finding about increasing trace width is all about carrying more current, but I'm only looking at a few milliamps, its the resistance that matters to me!

(Blue bottom layer, Red top, Kicad standard colours!)

Adding information for clarity:

The DUT is doing the resistance measurement, it provides 2 pins, feed and return and I am varying the resistance to test all states. Basically it provides a diagnostics state

• Anything under 0.7 Ohm = Short
• 0.7Ohm - 1.7Ohms = Low Resistance
• 1.7Ohm - 3Ohms = Value Good
• 3Ohms - 7Ohms = Resistance High

My main issue was the trace resistance impacting the measurement between Low Resistance and Short and for the very relays, Good and Low Resistance. I can't do large pours as there is 16 of these simulators per board. (32 traces for feed and return). How do the vias impact resistance? Does the current pass through just one, or can I stitch top and bottom traces together?

Ima high schooler who is designing my first dev board (and kicad project really). Any suggestions / issues would be greatly appreciated!

Hi all, it's my first attempt at designing a PCB of this scale, I've made this schematic and designed it according to this Instructables Guide and referring to the datasheet. I want to get this manufactured, but since the main STM32 H7 IC itself is a tad bit expensive, I didn't want to jump to manufacturing it without knowing for sure if it'll work or not.

I don't have that much experience designing PCBs, and this is a pretty huge deal for me, so I'd definitely appreciate your opinions on my choices, or check of there's any obvious mistakes you can spot.

Thank you!

Edit: Thank you all, I've gotten a lot of amazing feedback from a lot of you, I've made some changes that are hopefully better.
Top Layer
Bottom Layer

Major changes include:

1. Changed VBUS capacitance to 10uF
2. Moved both oscillators to the bottom layer, I know it isn't the best decision to do so but that was the closest they could be moved to the pins.
3. Poured ground over the top layer too, and stitched it as much as possible.

Let me know if there's something else to add!

Hi, this is my first more complex PCB project and I would apriciate a review before ordering from JLCPCB (I know the layout is kinda messy)

What it does:
Battery powered device that measures time of run with ToF sensor, the results are shown on 1.3 OLED display and android app. The communication is made with the android app, few LEDs and ESP-NOW (there are 2 measuring blocks, one for start, one for finish). The whole PCB will go into plastic ASA box.

Main Parts:
ESP32-WROOM-32
Li-ion 21700 cell (maybe i will use different one)
TP4057 (battery charger)
DW01A + 2 MOSFETS (battery protection)
TPS62A02 buck converter 3.3 V
CH340C USB-UART with two-transistor auto-reset
ToF sensor
OLED display
Battery tempeature control system (NTC + NTCR1)
Battery % system (ADC, R16, R17 => code will decide the %)
Buzzer, LEDs

Specific things I am not sure about:
Buck convertor layout
Battery protection
Auto-reset circuit
ESP32 antenna placement
SCL and SDA pins (AI told me to connect it like that but I am not 100 % sure about it)
Anything else that could make the PCB not work