r/PrintedCircuitBoard

Hi everyone, I'm looking for an extra set of eyes before I send this board out for manufacturing.

This is an Arduino form factor ESP32 development board that I'm designing for general-purpose embedded projects. The goal is to use it for LED projects, environmental and sensor monitoring, and as a training platform for school students.

I'd really appreciate any feedback on the schematic and PCB layout, especially anything related to manufacturability, routing, grounding, power distribution, decoupling, silkscreen, or anything else that stands out. If you notice something I've overlooked, please let me know.
I have included everything including Schematics and BOM.

Thanks in advance for taking the time to review it!

Just want to get generic feedback of if you think this is ready for production or not! This is an STM32 controlled flight computer with an IMU and battery charging (2S) that stores data on a microsd card. I tried to make it as compact as I could (35mmx45mm)

Hello, its me again. I made some changes to the buck circuits and left some alone.

• I saw one of the comments on my previous post mention reducing part count, so I decided to switch to the LM5143 Dual Synchronous buck IC in hopes to reduce part count.
  • The original EVM reference I used was a 6 layered board, I somehow managed to squeeze it down to a 4 layered board to reduce cost.
• I also cleaned up and tried to not let let the green traces on the schematic overlap. there's 1 overlap. hopefully that's acceptable
• I still cant quiet figure out what how many MLCCs I actually need, so I just took a guess. The quickstart guide wasnt much help in that regards, but it was very helpful in determining the values of everything else.
  • I asked multiple AI/LLM on how many i actually needed. They started out with an absurd amount (700uF wow), and eventually got it down to about 200 after questioning its logic for a bit (ended up trying to follow the evm amount).
• I used 12A as a reference for the quickstart guide. I probably wont ever reach that much, but the overhead should prevent edge cases.
• Im not quite sure If that one lone aluminum 100uF capacitor is needed. AI kept saying I need it so I kept it there.

Please let me know If I should add anything. any critique is appreciated. I hope the image are clearer this time. last time was kinda blurry.

rough specs:

• 5v @ 12a
• 3.3v @ 12a
• 5vsb @ 5a

Hello, It is my first time doing PCB design for my project, I am currently designing a boost converter using the TPS61023DRLR IC and want some feedback for it before I order it from JLCPCB.

Essentially I have just created three pours on the F.CU layer for VOUT, VIN and GND as seen in the layout example and then used via stitching on the gnd pours to connect it to the B.CU layer which is all GND (Blue). This is my first time working with pours so I'm not really confident if this is how it should look like so I would like a check if possible before I order the pcb.

The MCU is really small so the copper pours didn't allow me to like fill into the individual pads which is why I solved it by just making traces to the pad to the pour, I don't know if I should do this though (Image 3)

Here are relevant links:

Datasheet for IC

Hi everyone. I am planning to replace the 10 GPIO header pins on my current pump controller board with a GPIO extender, such as the MCP23017, so the control goes over I2C.

The "GPIO" variant (mosfet/pump/12V circuits) was already reviewed and produced; the change from direct GPIO -> I2C control is new here and is the focus for the review.

The plan is to go from a Raspberry Pi (or another SBC with I2C) to the board via I2C, and potentially daisy-chain another device, like a NAU7802, for scale control.

Since I do not have a strong background in this whole PCB topic, I mostly have dangerous half-knowledge and would love some feedback. Things I am not sure of:

• Adding a (100nF?) capacitor to reset for stabilisation
• Adding a pull-up (4.7k?) to SDA/SCL; I think RPi already has some?
• Is this daisy-chaining okay
• General (routing/schematics/other) mistakes a rookie makes

The PCB (pcb/cbb-i2c) source is also available on GitHub if anyone prefers looking into it over the editor.

Thanks in advance for your time.

Hey! Currently working on a large board and im wondering about my connections.

also wondering about the sizing cap. my motor literally does not have an inductance value on the datasheet so I'm not able to calculate it. the datasheets recommends 100uf as a minimum value so I assumed something like 330uf would be fine.

I know its messy, it's currently in progess. I plan to have nFault and nSleep faults for all four motors connected together, as a rev1 my goal is to have something DRIVE. So if something happens to one motor, turn everything off, etc.

I'm wondering if anyone can take a quick glance at this and name anything very very wrong with this, and please take a look at my motor controller IC's to see if that's ok. I'm planning to power this board with 25v something like a 6s or something. Vref = 1.98V to stop current at 3A. for reference, my motors are:
https://www.pololu.com/product/4693

thanks!

I am designing this 2 layer PDB for 4 motor drivers and 12V OUT, i would like your opinion and suggestions on ways of improvement. The PDB features current and voltage monitoring.

Hi all, I am designing a PCB for a soldering fume extractor. I plan on using a 4 pin noctua fan, and a 4S battery to power all this.

I am using a 555 timer to generate pwm for the fan, 20V usbc to a PMIC for charging the battery. The comparator/resistor battery gauge uses tested values that seem to work. The potentiometer has a switch, so when enabled will make the mosfet trigger the fan on, while still adjusting the speed with the 555 timer. I would really like to also know about my layout as this is something I am working on. This is also my first USBC design. Also, this uses Vcuts to make two circuit boards, the plan is to use the 3 pin connectors from the two boards to connect them together to get the battery gauge. Anyways, let me know what you think!

My PCB schematic and layout: https://imgur.com/a/aa5a78q

PMIC 4S Charger IC Monolithic MP26124GR-Z
USB-C PD Chip TI TPS25730DREFR (20V 3A output in the design)
STmicro 4 Comparator IC TSX3704IYPT
NCH MOSFET VISHAY SIS406DN-T1-GE3
5V VOLTAGE REGULATOR LDO AS78L05RTR-E1
TI ADJ BUCK CONVERTER (12V output in the design) LMR51450SDRRR

Hey all, since my last post yesterday, I've made some big changes. For one, I made my PCB 4-layer with the internal layers being solid ground planes. Furthermore, I added two capacitors after the ferrite bead. I also added stitching vias around the entire board (does it look good?), as well as adding a TVS diode right by the USB port for ESD protection. Is everything looking correct?

For those that're new, I'm making this STM32 controlled flight computer as compact as I can (35mmx45mm) while trying to fit in a bunch of cool features. Let me know what you think!

Hello everybody,

I've been working on a UAV flight controller that I intend to run Ardupilot on.

You can find the Project here for the pin configuration on STM32CUBEMX here. And for BOM here.

Note: the Layout in the github file is not ready at all.

I tried to make the design as modular as possible, meaning that most of the job done on the FC is to distibute power to the modules (RF reciever, GPS etc.)

and control ESCs (Electronic speed controller) and Servo motors.

- MCU:

The MCU I selected is highly capable STM32H7 series with a 100 pins. I saw a lot of similar designs using It so I used it.

- Sensors:

I'm using a ICM-42688 IMU + Gyro and a MS5611 barometer and temperature sensor for altitude. Just like the MCU I saw lots of designs using It and the sensors are Ardupilot compatible, They're also available at local distributers and not too expensive, Although I'm considering the following for SPI lines:

1- Adding pull-up resistors to the SPI lines.

2- Adding series termination resistors.

3- Matching their length in the Layout.

I'd be very happy if you can provide articles, studies in regard of these topics.

- Connectors:

The connectors I'm using are not included in the BOM, because I haven't quite decided yet but I'm considering the following:
- JST-GH (1.25 mm pitch): for everything except for the RF tranciever and power connector.
- Molex Clik-Mate (2 mm pitch): for power and RF tranciever, particularly because it can handle higher currents.
-For the PWM and Dshot I'm considering plain pads that I'll solder some wires on. (btw pwm is used for the servo motors, and Dshot is for ESCs).
- For the SD card I'm also considering pull up resistors and length matching in the layout just like for the sensors.
- I'll be probably using a GPS + magnetometer module (something like the BN-880).

- Pitot tube, Reciever, RF tranciever, Aux Computer connection (sometimes an additional computer is used for image processing etc.) and LIDAR are all standard.
- I'm also considering adding termination resistors to the UART lines, the resistors you see are a result of me consulting Gemini and I'm not sure about them.

- Power:

For the power I want to be able to power the board both from a USB-c port and from a power connector, I'm considering powering the board from a pixhawk power module. I'm considering adding higher capacitance to the input as a DC-linkish.
I have two seperate 3.3V outputs, one from an LDO that will power the digital part of the board (SD-card, MCU VDD pins) and the LDO will power the analog part of the board (sensors, GPS module).

If you have any questions please ask. And I welcome any recommendation :).
This is my 3rd PCB btw.

Hey all, just wanted to get this reviewed before I sent it off for production. I tried to make things as small and compact as possible, so there is a lot of vias and tight traces. Thanks!

Hi! As an embedded software engineer making my own PCB is a pretty big milestone, and I have lots to learn! Please be severe but kind :)

The project is a Bluetooth Low Energy (BLE)-enabled magnetic switch sensor powered by a CR2450 button cell battery. Tested on a development board, now I need something "real" I might eventually develop as a real product (one can dream!).

My design requirements/constraints:

1. Small form factor, prioritize thinness over XY footprint
2. Long battery life: (hence, why I picked the Reed switch, rather than a hall effect sensor, and why the somewhat oversized CR2450 over the more standard CR2032).
   1. The device will deep sleep 98%+ of the time, wake up to capture a few edges, then go back to sleep. Daily or weekly data transfer to Home Assistant or Smartphone.
3. The expected reed switch switching frequency is very low: maximum ~10Hz in short bursts on occasional daily use.
4. Transmit power will be set as low as possible to maximise battery life, wireless range is not a priority on the application I have in mind (a few meters is fine).

Main worries:

1. Will it power up
2. EMC emissions
3. Battery life (is there anything that could cause leaks).

Notes:

The two capacitors were selected based on:

1. The chip vendor required one mandatory 10uF
2. Bursts of BLE transmission don't do well with button cell batteries due to their high internal resistance.

Given the somewhat simplicity of the device, I might be fooling myself in thinking I don't need any other components.

Thanks!!

Hey folks, a review of this board would be appreciated.

There isn't much on this board, the two main components are the ECP5 45K variant (caBGA256) and a W9825G6KH SDRAM. My main concern is with how I routed the SDRAM chip to the FPGA. It can run at a maximum of 200mhz, and I did not account for length/impedance matching while routing it. Things like power filtering or extra components can be implemented on whatever board this would attach to.

I'm very new to the high-speed electronics world, so advice would be great.

Thanks!

Hello, I'm creating a PCB for a thrust vector control rocket. I'm utilizing a MPU6050 gyroscope/accelerometer, a BME280 altimeter, Adafruit Breakout SD Card Writer, MPM3610 DC-DC Buck Converter (output 5V), LM2596 DC-DC Buck Converter (for servo power, output ~6.5V), and an Arduino Nano Every.

I'm pretty worried about I2C noise corrupting sensor readings, so I've included decoupling SMD (0.1 uF) capacitors for the SD Card Writer, BME280, and MPU6050. Additionally, I've used THT capacitors (1000 uF) for the LM2596 output, as well as across VIN and GND of each servo motor.
Included are 2 status LEDs for the MPU6050 and
SD Card writer, with a 100 ohm resistor wired in series with each.

For the power supply, the battery input will take ~7.5V, where the line will be split, one fork to the MPM3610, which will step down to 5V for Arduino and Sensor Logic, the other to the LM2596, which will step down to ~6.5V for servo power. I did this to avoid large voltage spikes that could corrupt sensor readings, which would likely damage the sensors.

I utilized a F.Cu and B.Cu copper pour on the PCB, with stitching vias along the perimeter of the board, around the GND pins of each servo, and around each sensor module. I'm a little concerned about the presence of any islands, but can't spot any from just observation and the net highlight tool.
Trace widths are 0.6mm for battery input, 1.5mm for servo power line, 0.6mm for 5V general power, and 0.2mm for signal traces.

The DRC renders 0 errors and disconnected pads, and to the best of my knowledge, each sensor interfaces with the Arduino Nano Every correctly.
Any problematic areas anyone could spot, or advice I could be given, would be greatly appreciated. Thank you so much!

The controller is mainly for fading effects using a variable duty cycle PWM, at most 1A of continuous current, most of the load it gonna be the ledstrip.

Power source is a lipo battery, 3.2v to 4.2v

I can't figure out how to manage pcb length, so its short but also keep the mcu away from the regulator to reduce EMI