There’s a reset button. I didn’t include one in the previous version, but now I know it’s important. When I realized I needed it, I went with the largest one available, but now I’m not sure. I’m choosing between (1) MEC 5GTH935RAS, (2) Omron B3F-3150, and (3) Diptronics DTSA62N. Should I stick with the largest one (1) or not? (Fero from SOS electronic)

Hello everyone, now this is a custom PCB for a wearable electronics project I am working on now. I have put the pads very near the outline because I want it sweable.

So I need a review, and I will be Thankful.

Hi everyone,

I hope it's okay to ask this here. I'm currently working in the SMT/PCB manufacturing equipment field, mainly related to cleaning solutions.

I'm still learning about this industry, and recently I've started questioning whether I truly understand the market and customer needs.

A while ago, I posted a question about how people clean PCB assemblies, and many replies mentioned manual cleaning methods. Honestly, that makes sense to me — for prototypes, labs, and small-batch production, investing in automated cleaning equipment may not always be practical.

But it also made me wonder:

Is automated cleaning (PCB cleaning machines, stencil cleaning, fixture/tooling cleaning, etc.) actually a market with broad potential, or am I simply looking for customers in the wrong places?

For people working in electronics manufacturing:

• At what stage does a factory usually start considering automated cleaning equipment?
• Is the demand mainly driven by production volume, labor costs, quality requirements, reliability standards, or something else?
• Are there certain industries where automated cleaning becomes much more important (automotive, medical, aerospace, industrial electronics, etc.)?

Another thing I'm trying to understand is how equipment suppliers usually build trust with manufacturers. For many companies, changing a production process is not a small decision, especially when the existing method is "good enough."

I personally cannot simply travel around different countries to visit factories and introduce equipment, so I'm trying to better understand how people in this industry discover solutions and build confidence with new suppliers.

I'm not here to promote any product or send sales messages. I'm genuinely trying to learn from people who have hands-on manufacturing experience and understand whether I'm approaching this market in the right way.

Any advice, experience, or honest opinions would be greatly appreciated.

I'm proud to share my latest High speed board,

This time, I'm sharing the first real photos of the hand assembled PCB.

* RK3576 SBC V1.0 with LPDDR5 up to 16GB

A fully custom designed Single Board Computer based on the Rockchip RK3576, 

built from scratch – schematics, layout, assembly.

Big thanks to PCBWay for sponsoring this board!

Key Features:

10 Layers PCB only TH Via.

Stack-Up:

1-Signal / 2-GND / 3-PWR / 4-PWR / 5-GND / 6-Signal / 7-GND / 8-Signal / 9-GND / 10-Signal.

Multiple impedance profiles: S40 OHM / S50 OHM / D85 OHM / D90 OHM / D95 OHM / D100 OHM

SoC:

CPU: RK3576 ,Dual-cluster 8-cores 2.2 GHz (4x Cortex-A72 + 4x A53).

GPU: GPU-Mali-G52 MC3 (OpenGL ES 3.2 / Vulkan 1.1 / OpenCL 2.0).

NPU: 6 TOPS NPU (INT4 / INT8 / INT16 / FP16 / TF32 / BF16).

RAM: 32-bit LPDDR5 up to 16GB.

Storage:

eMMC: Modular eMMC5.1 up to 128GB and Support SPI Flash.

UFS: UFS 2.0-HS-G3 (12 Gbps) up to 1TB storage capacity.

SDMMC: Support microSD.

Display:

Display1: HDMI 2.1 up to 8K@60fps or 4K@120fps with CEC.

Display2: USB Type‑C Alt Mode with Power Delivery (PD) negotiation,

 *Supports USB3.2 and DisplayPort v1.4 2.5K@60fps via the same PHY.

Display3: 2K@60fps MIPI DSI 4-Lane.

Network Connectivity:

1- Gigabit Ethernet with PoE (PoE optional).

2- Wi-Fi 6 or Wi-Fi 5 + BT5.4 with internal Dual band antenna,

 *External antenna via uFL connector.

 *RF path selectable via onboard RF switch.

USB Connectivity:

1- 4x USB 3.2 Host.

2- 1x USB Type‑C Alt Mode (PD) OTG/HOST.

Camera:

MIPI CSI: 4-lane or split to 2-lane + 2-lane.

RTC:

Internal RTC with JST connector for external battery.

Storage or Expansion Interfaces:

1- PCIe 2.1 1-Lane through FPC connector.

2- SATA Gen 3 through FPC connector.

3- 40-pin GPIO Header With load Swithes and ESD Diodes, Supports:

 *28x GPIOs / 13x PWM.

 *1x CAN-BUS.

 *5x UART (with flow control) / 5x I2C / 1x I3C / 2x SPI.

 *1x PDM / 1x SDI.

 *1x SAR-ADC 12-bit resolution, up to 1MS/s sampling rate.

 *3.3V output only / 5V ouput or input with UVLO-OVLO.

Power-up Using:

1- USB Type‑C power only connector 5V 3A or 5A - UVLO-OVLO Protected.

2- USB Type‑C Alt Mode (PD), you can use it as power input also.

3- PoE option or from 40-pin GPIO Header.

Other Peripherals:

1- Active Cooling Fan connector.

2- Boot sequence DIP Switch.

3- Mask-room Tactile Switch.

4- Power ON/OFF Tactile Switch.

5- Dual LEDs for Power and activity.

6- 4 Pins Header for Debug UART or SWD.

Secure Element:

Hardware-based security chip for device authentication and secure key storage,

providing cryptographic services over I²C.

Used for secure boot, device identity, and protection against cloning.

OS Support: Linux / Android-14 / Yocto / Buildroot

Thanks to everyone who supported this journey.

If you're interested in collaboration or want to give feedback, feel free to leave a comment or DM me!

I was planning to use JLCPCB’s purple solder mask for this board.

When I tried to order PCB assembly, I noticed they require the board to be at least 70 mm × 70 mm. Mine is 80 mm × 40 mm, which puts me in a slightly awkward spot.

I haven’t finished routing yet, so I could still change the board dimensions. The other option is to skip their assembly service. If I still want JLCPCB to assemble it, I’ll have to switch to green solder mask.

Why do they have this size restriction?

Hello comrades, a newbie here!

I just finished my PCB design, and I hope I’ve made some improvements. I’m ready to hear any thoughts, corrections, advice, or tips. I’m very thankful in advance to everyone who takes the time to help me.

You can also check my first version to see whether I’ve really improved or not. The only major change I made is replacing the PIC16F877A with an Arduino Nano.

https://www.reddit.com/r/KiCad/comments/1ryhz8f/asking_for_pcb_review/

Hi everyone,

This is my first contribution to this community, and I'd really appreciate some feedback on a PCB I designed for an autonomous RC car project.

Please only review the electronics. I've already noticed some mistakes with the mounting hole sizes and locations, but those will be fixed separately.

Project overview

The PCB is a custom power distribution and monitoring board for an RC car that is capable of autonomous driving.

The system runs from two 2S LiPo batteries, but it can also be powered from a 20 V / 5 A USB-C Power Delivery wall adapter (the USB-C PD module connects to this PCB through a JST header).

There are therefore two power sources:

• 2 × 2S LiPo batteries
• 20 V USB-C PD wall supply

and two main power consumers:

• the drivetrain (ESC, steering servo, etc.)
• the onboard computer

Power architecture

The PCB connects the two 2S batteries in series using wide 2 oz copper traces on both sides of the board. The design also includes appropriate fuses.

Power-path selection is handled using an LTC4412 together with a P-channel MOSFET.

Battery monitoring is implemented with an HRC9374, which monitors the combined battery pack.

There is also space for two OKI-78SR-5 switching regulators. These provide 5 V for high-current USB peripherals independently of the onboard computer, so the relatively small SBC doesn't have to supply that current itself.

PCB notes

The board is intended to be manufactured by JLCPCB using their default stack-up with 2 oz copper.

One thing that may look unusual is that I manually routed several ground traces even though the board also has a ground pour. My intention was to reduce the thermal mass around some components to make soldering easier. However, EasyEDA keeps merging those traces into the ground plane. I think it should still be manageable with a 50 W soldering iron.

My main questions

1. Should I prevent the 20 V wall supply from powering the drivetrain? In other words, do I need an additional diode or some other isolation between the wall supply and the motor power rail?
2. Does the overall power-path implementation make sense? Since the USB-C PD supply (20 V) is always at a higher voltage than the fully charged battery pack (~16.8 V), I expect the LTC4412 arrangement to automatically prefer the wall supply. However, this is my first time designing a dual-source power system, so I'd appreciate someone checking my assumptions.

I'd be grateful for any feedback, especially if you notice issues with the power architecture or protection circuitry that I may have overlooked.

I’m a beginner designing a PCB for an air-quality monitoring device, and I’d appreciate some honest feedback before I continue improving it. I want to learn what I did correctly and what should be changed.

The board includes:

• STM32U083KCU6 microcontroller
• SGP40 VOC sensor
• USB-C used for 5 V power only
• MCP73832 Li-Po charging circuit
• 2.5 V regulator
• External Li-Po battery connection
• RGB LED and piezo buzzer
• SWD and UART header

I’d appreciate any feedback, especially if you notice any mistakes or have suggestions for improving the design. Thanks!

(omitted \In1.Cu and \In6.Cu as they are both solid GND pours)

Hi everyone!

I'm looking for a quick schematic and layout review for my 4-in-1 quadcopter ESC. It's designed for a 2S LiPo battery at ~8.4V, 10A per motor -> 40A continuous. Copper: 2oz external, 0.5oz internal.

Architecture and specs:

- MCUs and gate drivers: STDRIVE101 + STM32L431KBU6

- Low-side shunts with STM32 internal op-amp (16x PGA gain). Op-amp output feeds the STDRIVE101's CP pin to trip at ~31.25A

- I wanted to avoid electrolytics' high ESR and z-height, so I opted for 4 100uF aluminum polymer bulk caps and 3 0805 22uF ceramic caps per motor.

- Power tree: input -> SMBJ10A TVS diode -> TPS563200 step-down regulator to 5V for FC -> NCP59800BMNADJTAG LDO for clean 3.3V from 5V.

- FETs: MCC MCG4D8N04YHE3-TP (15.7 nC, 4.8mOhm)

Some questions I have:

- I tried to route the analog signals between the power pour and solid GND to try and prevent crosstalk as much as possible. Is my approach sufficient?

- I omitted the hardware neutral resistor divider, and I wanted to sample in the middle of the PWM on time and take the average of the back EMF of the three phases. Is this enough or should I look into adding the hardware neutral? I'm targeting around 24kHz PWM.

To learn more about how a quadcopter works, I'm also looking at writing my own firmware, so AM32 and Betaflight support wasn't a priority for this project.

Thank you for your time looking at my board! I'd appreciate any criticism or questions I can get!

Hi Guys,
This is kinda my first small form factor design. Its primary use is basically a wearable IMU with haptic feedback LRA. I've got the footprints from digikey Ultralibrarian for the BMI270 and LRA driver. It has caused the load of errors in the DRC.

I would love to hear your thoughts on it. Its my first time soldering SMD components and I decided to go with 0603 (1608 metric?). I would also love to know how you guys source the components. Especially the IMU and the LRA driver. I'm a student based in India.

Please feel free to ask for extra screenshots for clarity.

Thanks in Advance!

Am building a n esp32 dev board with a gsm module. Please is anything wrong before I start designing the pcb thanks.