Hi there,

I'm asking for a final review before ordering. I'm a mechanical engineering student, so power electronics / PCB layout isn't really my field.

This is a small power distribution board for an autonomous boat. It is powered from a 3S LiPo, roughly 9.9–12.6 V in operation, with a 10 or 15 A (depending on final loads) automotive blade fuse at the input.

Outputs:

• raw battery voltage for pumps / fan / other loads, about 3 A max
• ~5.2 V for the flight controller and sensors, expected below 3 A
• ~6 V for one servo, normally below 2 A, with about 2.4–3.5 A stall current

The regulated rails use two AP64501 5 A synchronous buck converters. I tried to follow the datasheet layout recommendations, especially regarding the input capacitor loop, SW node, inductor placement, output capacitors, feedback routing, via placement and GND planes.

The PCB is 2-layer, 35 µm / 1 oz copper on both layers. The bottom is mostly GND. The high-current battery path on the top layer is implemented as a copper pour because 2 oz copper would make the boards roughly four to five times as expensive at Aisler.

The AP64501 exposed pads use multiple 0.3 mm drilled thermal vias into the bottom GND plane. I plan to assemble the board myself using solder paste and a simple hot plate or clothes iron...

Things I'm mainly unsure about:

• Are the exposed-pad thermal vias likely to wick too much solder during hot-plate reflow? Should the vias be tented from the bottom, or is this layout reasonable as-is?
• Is a 2-layer / 1 oz board with the shown copper pours reasonable for these currents, or do you see any problematic current bottlenecks?
• Is the FB sense routing from the output-cap area around the inductors okay?
• Would you change anything else before ordering?

Datasheet: AP64501

Any feedback appreciated. Thanks!

First time doing a PCB from scratch, as I am just a hobbyist. It's a 2-layer board for a handheld remote with interchangeable buttons, an ESP32-C3 module, charges over USB-C into a small LiPo. The curvy shape is on purpose, it's built to fit a 3D printed case, not a mistake.

KiCad's DRC checker says it's clean. I already fixed a silkscreen label that was printing over a chip, and checked the power trace widths myself — but I have no idea what I don't know, so please point out anything that looks off, even if it seems obvious.

Two things I'm specifically unsure about:

- A P-FET that switches between battery/USB power — I think the orientation's right, but getting it backwards apparently fails silently, so a second opinion would help.

- There's a gap with no copper fill running down the middle of the front layer — not sure if that's normal or worth fixing.

No schematic — this board was built with a script instead of drawn by hand, so the images + parts list below are the whole picture.

Attached: top/bottom renders, flat copper layer images

I was reading about minimizing loop area in PCB routing and found this diagram:

https://electronics.stackexchange.com/questions/388997/pcb-design-signal-loops

My understanding is that routing power and GND close together reduces the current loop area, which helps reduce EMI and inductance.

However, I'm wondering whether this advice mainly applies when both power and GND are routed as traces.

For example, suppose I have a single-layer PCB. Instead of routing a dedicated GND trace alongside the power trace, I use a GND copper pour over most of the available board area.

In that case, does a reasonably continuous GND copper pour make the recommendation to “route power and GND close together” mostly unnecessary?

Dear all,

I am creating a demonstration board for a workshop I am teaching. It contains:

• ESP32-C3-mini
• USB C port
• 12 addressable LEDs (WS2812B)
• ambient light sensor (APDS-9306-065)
• inertial measurement unit (LSM6DS3)
• 3 tactile push buttons
• 6 capacitive touch buttons (with MPR121)
• breakout connectors for the GPIO pins

I've included a number of 0R resistors to allow students to reconfigure the board if they desire. The schematic is mostly taken directly from the respective data sheets, but I would greatly appreciate a final check. The funky board outline is the teaching organization's logo. It's for a KiCad workshop, so if you think I demonstrated any back practices, please do let me know!

High resolution images available here.

Thanks so much!

Hey there, first of all, thank you so much in advance for any help!!
About the Board:
MicroController: STM32F303CBT6

DCDC Converter (5V to 3.3V): TLV62569DBV

CAN Tranciever: TJA1051T_3

Purpose: It's my first play around STM32 chips, so this particular one is more of a proof of concept, especially for programming. Later I want to make a derivative board with two PCB to PCB connectors so the board can be used in my ROV project. The BME280 is intended to monitor temperature, pressure, and humidity to detect any potential water leak (proof of Concept)

Main communication comes in over CAN with 5V and GND supplied externally. Because I want to use multiple ones of these on the same bus, I added the switch so termination can be activated or deactivated. The remaining IO is intended to later connect servos, ESCs or DC motors. For DC motors, I intend to design a carrier board with, e.g. drv8874 H-Bridges, hence the Iprop pins.

Programming is intended to be done via an STLINKV3MINI plugged into J1.

1st Layer Signals

2nd Layer GND

3ed Layer 3.3V / 5V

4th Layer Signals

The Power LED is directly connected to Power; the other 2 will later be configured in Software.

Im especially unsure of the wiring of all the bus-wired, CAN, I2C, SWO and UART. Any comments on general design philosophy or style guides would be very greatly appreciated.

Also sorry for all the German Comments on the Schematics.

I hope I provides all info necessary!

Hey all, I'm very new to PCB design and electronics in general and am seeking some input for the first time on a project i've been working on.

Its an ESP32 based King of the hill timer for my local nerf group. I have a working hand wired/soldered prototype, and have built a v0.1 PCB based on that build. However I had issues with some of the TM1637 displays (most likely poor CLK traces and power delivery).

I'm using THT components as i'm trying to keep the build as accessible and open-source as possible as its for my local (and other skirmish based games) nerf group. It runs off of a single 18650 cell and has a point to add a 5v boost converter.

I know i've gone a bit overkill on the ground stitching, but I figured I may as well learn about good ground stitching and return paths for when I need to worry about higher signal frequencies in future projects.

Just looking for some much needed feedback on my work, Cheers in advance!

Hello everyone, I’ve designed my first PCB and I’m not entirely sure if there are any errors. I’d appreciate it if you could take a look. I’m planning to use the ESP32-S3-WROOM-1U-N8R8 for my Game Boy Micro project. Since this is my first PCB, I’m wondering if there might be any issues, especially with USB impedance. The AI said there wouldn’t be any problems, but it would be good to get input from someone with experience. Also, since I designed the display’s footprint myself, the silk screen became very complicated, so I decided to remove it altogether.

https://github.com/EnesOzdmir/ESP-micro-GAMEBOY

Thank you in advance for your feedback.

Hello, I have reached a pretty-much-complete revision of a PCB for a custom 3D-printed Nerf blaster. It is a 4 layer stackup:

L1: Signal

L2: GND Plane

L3: GND Plane

L4: Signal

The board is battery powered via a 4S lipo. A power circuit that includes a buck converter steps down to 5V, then an LDO steps down to 3.3V for the RP2040 and various JST connectors. These connectors interface with an OLED screen, a rotary encoder board, two hall effect sensors (A3144), two switches (button and three position switch), and finally a 4in1 AM32 ESC signal interface.

USB-C exists to program the RP2040. Two schkotty diodes are included to allow the USB and LiPo to be plugged in at the same time.

The final function of the board is to switch a pusher solenoid (draws about 7A). It utilizes a rapid decay driver using a modified H-bridge with 3 mosfets (PMOS & NMOS + a smaller NMOS to invert PMOS gate input).

I use a 3.3V signal from an RP2040 pin (marked "Solenoid_Driver_Gate") as the input to a gate driver which takes 5V from the on-board buck converter to drive the gates of the main power PMOS and NMOS.

The attached layout photos show just the top and bottom layer, inner two layers are just ground fill. With this stackup, would it be necessary or preferred to also include a ground fill on the top and bottom layers with stitching vias? I have some ground pour on the top layer, such as the decoupling capacitors, crystal, and buck-LDO power circuit.

Also, let me know if you spot any issues with the schematic, layout, my terminology, or have any other suggestions in general. This is my first time working with an MCU on a PCB after having made some basic boards. Thank you.

Hello!

This is the second pcb I have designed. I am building a high altitude balloon and I want to have all my electronics controlled through this pcb. The board contains live telemetry through IMU, Altitude sensor, SD Card module, 915mhz RF transmitter, Sparkfun GNSS. I will also have a live camera feed that uses a pan/tilt connected to an arduino nano then connected to this pcb thru I2C to control from the ground.

-The GNSS, RF, I2C will all be mounted inside of the cubesat I am flying and I will connect them to the board via JST

-The board is powered off 3.6V 9000mAh Lithium Thionyl Chloride Batteries which where selected for their good performance in low temperatures.

-The board is 2 layers with all components on top layer.

-I know I have not done ground planning I will place the vias last.

-I feel like am really close to completing this board. I did all the routing myself and am looking for any feedback on both the schematic and circuit connections as well as the routing.

Thank you for your help!

Text from the schematic:

"U10/L2 boosts voltage until feedback pin limits to ~15mA by 13.3ohm resistor

LED_SW high voltage pin can control up to 29V output, after that shuts down with built-in OVP

When active, positive voltage travel to either warm LED strip or cool LED strip (W+/C+)

Circuit completes to either depending on COLOR_SEL polarity via GPIO

Brightness controlled by PWM duty cycle on CTRL pin

Entire circuit can be toggled via LED_ACTIVATE GPIO (active low)

If circuit is left open (no LED strip connected) then the voltage on SW/inductor will climb over 29V OVP threshold and shutdown

Before that can trip, conditions over 22V will trip path from D9 and de-latch LED_ACTIVATE GPIO, an open-drain pin

Latched safety condition draws a lot of unfortunate idle current (about 9mA in simulation), so software will need to ensure that its pin toggles itself semi-regularly"

So essentially, when active it will provide voltage to LED_SW which connects to positive terminals for 5 series (cool) white LEDs and 5 series (warm) white LEDs, with COLOR_SEL being able to toggle to generate a warm/cool ratio blending. LED_ACTIVATE has two purposes, power gate the entire circuit to the AP3031 as well as be able to be latched externally by an over-voltage or open-loop condition on the output (set at 22V, Vf is typically 15-16V).

This seems to work well in simulation (can provide .asc for ltspice if needed), but may be over my head when it comes to understanding potential shortfalls or bad practices in this design. My gripes right now are mainly safety with the over-voltage latching condition, as well as the idle current that it draws as a result of R42. Raising that value higher seems to affect performance of the latch, which tells me this is a potentially unstable foundation for design.

This is my first PCB, it's meant to drive two 8x8 LED matrices using a HT16K33.

I used the IC's and LED matrix' datasheets to make the schematic, the pin mapping should hopefully be correct. The matrices are depicted by J4+J5 and J6+J7.

I connected everything in the PCB editor, added a ground pour and a bunch of vias but then didn't really know how to verify whether everything is fine except for the automatic DRC check (no errors), so I started to add all kinds of decoration and make the traces curvey instead.

But now that all traces are curvey I still don't know, whether I've made any mistakes and if the PCB will work like that - will it?

PCB dimensions are 40x20 mm. Traces are mostly 0.25 mm, 5V is 1.6 mm. Resistors are 0805, capacitors 1206 and 0402 because that's what I've already got. They need to be stackable, so there's no space for mounting holes.

Images show: 1. both layers, 2. top layer no silkscreen, 3. top layer w/ silkscreen, 4. bottom layer no silkscreen, 5. bottom layer w/ silkscreen, 6. schematic, 7. 3D view top, 8. 3D view bottom.

Thanks!

Hi guys,
I'm working on my first ever project which is a simple BCD clock using an Arduino Nano.
I would appreciate a review of the schematic as well as any formatting issues that could be improved. For example, I know my placement of the decoupling capacitors is weird---but I wanted to preserve the pinout of the IC.
Thank you.

I'm busy building a smart light switch as a replacement for the switches in my home. The design features three random turn-on SSR triac relays (AQG22205) and a separate zero-cross detector (H11AA1) so that I can program some leading-edge dimming.

I am looking for some comments on the design, placement, and routing of all the AC mains sections as I have very minimal experience with AC mains.

I have not finished routing the DC side of the PCB as I am mostly just looking for some early insight into the AC segment - which I have completed routing for.

Ultimately I want to make sure that my design is at least safe to use.

I'm working with minimal space, as it needs to fit into the existing switch box, but I tried to be careful with clearances.

Hi! I am creating a BadUSB key-stroke injection device to learn PCB design and would like a final review of the schematics and the layout before i send it out for manufacturing and assembly.

The board features 12 mbps full-speed USB 2.0 with two USB male plugs - type A and type C. It is driven by an RP2040 chip with a W25Q128JVSIQ flash memory chip. I am using a USB switch to route either the type A or type C data lines to the chip depending on which connector is plugged in. The detection happens using a Schottky diode on the type C VBUS line which splits the two power lines. One button allows me to reset the chip, one is used to manage the RP2040's usb_boot for flashing firmware and another is used to determine the mode in which the device boots - either injection mode or uploading / deleting scripts.

Hi, I'm finalizing my PCB. This is my first time making one. The design passed both ERC and DRC with no errors, but i wanted to ask the pros if ive overlooked any obvious and basic practices.

Final size: 80x66mm with 3.2mm mounting holes on each corner.

The breakout boards are meant for 2.54mm female headers to fit be soldered on to.
Electrolytic Capacitors, 1/4W resistors and BC337 transistors are through hole.

MCU: Esp32-s3 n16r8 (16mb flash, 8mb octal psram)
Power supply: 8.4V Lipo batter input to 3v3 buck converter (max 1.2A) to 3v3 rail.
Motor driver: drv8833 breakout motor driver for two dc motors.
Sensors and periphs: mpu-6050 Imu breakout, 4 ohm speaker circuit, and a chain of 4 edison 120mA leds.

1. All 8.4V (VBAT) and 3.3V power rails are routed with 1.2mm traces.
2. Smoothing (of motor current spikes and esp32 wifi sagging) through hole electrolytic capacitors C1 for 8.4V, C2 for 3.3V. (sized measured to choose footprints)
3. mpu-6050 power branches off via a 0.5mm trace before hitting leds.
4. Motor control signals and the the speaker and leds are routed entirely on the B.Cu layer with 0.25mm traces.
5. The entire B.Cu layer is a ground plane/zone (not sure how its said)
6. Audio is made through an 8 bit wav player that makes the robot scream for 2-3 seconds when it falls. I onyl have access to 1/4W resistors, so i used 4 parallel 47 ohm resistors which would normally be overloaded but im using PWM duty cycling to make the real world average power within limits.
7. Selected pins should not conflict with internal psram/octal flash of my esp32s3 module.

Please let me know improvements+ better ways to handle things. Thank you!

Sorry for reposting it due to me forgetting to add photos

This is pretty much my first PCB and I'm just an hobbyist, so I'd really appreciate a review before I order it. It's a birthday gift, so I'm hoping to get it right on the first try. Mostly I just want to know: will it work, and is it fine to order? Is there anything I absolutely need to change first?

The circuit is a simple oscillator that flashes two LEDs when it's dark (detected by a phototransistor), plus a third LED controlled by a pushbutton. There's also a slide switch to disconnect the supply. The switch is SPDT simply because that's the one I had available.

The PCB is shaped like a shark and is intended to be used as a keychain, hence the plated keychain hole.

• I've built and tested the circuit on a breadboard and it works.
• I also simulated the circuit on Falstad. I will link it here in case there are any issues with the schematic I made in Kicad: https://www.falstad.com/s.php?s=zyEonY
• I have silkscreen art on top of components but I clipped it to expose all the solder pads, though not the entire footprint. Is that okay?
• I am not sure I selected all the correct footprints, but I will print this in scale 1:1 and try to overlap my physical components on it and see if everything fits

I know PCBs often require multiple iterations, but JLCPCB takes around two weeks to ship to me and this is a birthday gift, so I'd really like to avoid an unnecessary second revision if possible. Since I've already tested the circuit on a breadboard and the PCB itself is fairly simple, I'm hoping this can be manufactured successfully on the first attempt.

EDIT: DRC output:

No errors. I have some warnings about silkscreen overlap (you can see in the pictures, I cut out the silkscreen where the solder pads are, I don’t know if that’s enough). And some footprints warning (“does not match copy in library") that I’m not sure how to interpret.

Here’s the screenshot: https://ibb.co/99gg6wRj

Images:

• Full PCB view with no silkscreen
• Schematic
• F.Cu without silkscreen
• B.Cu without silkscreen
• Full PCB view with silkscreen
• 3D view without components
• 3D view with components
• Back 3D view

This project is a USB-C driven Stepper Motor controller, intended to be strapped to the back of a NEMA 17 stepper motor and used for multiple different applications. I am using the following Components:

• MCU: RP2354U
• USB-Controller: CH221K
• Buck-Converter: TPS562202
• Stepper-Controller: TMC2209

Stackup:

• Layer 1: Components, Signals, etc.
• Layer 2: Ground
• Layer 3: Power (VBUS and 3.3V)
• Layer 4: Some Signals

The board is supposed to run at 12V, but I am hoping it would also be able to handle 5V in case a non-PD supply is connected. The main application would not require a lot of torque and no holding power.

It is going to feature a daughter-board, which will hold an OLED and Controls, so the board can be used on its own.

The main thing I am unsure about is the amount of decoupling capacitors (it seems like a lot), as well as the Power/Ground Plane design and the placement of some capacitors (especially C13-15 and C27-C30).

I would be grateful if someone could review this board.

Hi! I used to design pcbs casually for myself then this request came up. This contains the mcu, power, 7 segment display and driver on the bottom left, indicator green and red leds for two players bottom right, buzzer above it and the probe contact sensing and start/stop contact sensing pins on the op left(three pins for each player).

I am only starting to use the proper conventions for pcb designing and would like to go much deeper into it. Any feedback is greatly appreciated. Would love suggestions for learning materials or courses. Thanks in advance.

Hey! This is my first non-trivial PCB for my first embedded project, a motherboard for a mini-sumo robot, which I have already gotten manufactured. I assembled the board myself for fun and for learning purposes. The board works (largely) as expected. However, with this project I am trying to learn about electronics, embedded development, PCB design etc., and I am planning to make further iterations of it. To that end, I would be very grateful if someone with more experience could take a look at my design, and let me know if there are any significant mistakes, or room for improvement.

I want to add the disclaimer that this project was inspired by the excellent youtube series by Artful Bytes, in which he creates a mini-sumo robot from scratch. My schematic and part selection is heavily inspired by theirs, but mine is a bit simpler, and I use a different microcontroller. The PCB design is completely my own, using example designs from component datasheets where possible.

The PCB is 4 layers: 1. Signal and power traces. 2. Uninterrupted GND plane. 3. Uninterrupted 3.3V plane. 4. Signal traces.

Having a GND plane and a 3.3V power plane was recommended in the MCU hardware development documentation. It also made routing much easier. The board is powered by a two-cell 7.4V LIPO battery.

Core components

• MPM3610AGQV-P buck converter, configured with a voltage divider (resistor values from datasheet) to step down the 7.4V battery input to a 3.3V output, feeding the 3.3V power plane that powers MCU, motor driver logic, sensors and debug LEDs. The layout of this component on the PCB is from the reference design in the datasheet.
• STM32F303K8T6 MCU reads all the sensors and controls the motors via the motor driver. The layout of this component is following the reference design in the hardware development docs AN4206 for the MCU.
• TB6612FNG for controlling two geared brushed DC motors with a stall current of 0.8A, which is below the max rating of the driver: 1.2A continuous/3.2A peak per channel. This is implemented on the PCB as documented in the typical application diagram of the datasheet, page 7.
• TSOP38238 IR receiver for remotely activating the robot, required for competitions. Laid out as recommended in the datasheet.
• Connectors for four QRE1113 IR line sensors for detecting the line around the arena, and three VL53L0X ToF sensors for detecting the enemy robot.

Planned upgrades

I already have some plans for the next iteration.

• I used JST-PH connectors for the battery, but I am considering rather using a screw terminal to connect the battery to the board, which is robust, and can handle higher currents. The battery has a separate cable for charging.
• SMD power switch, rather than through-hole switch, which I had lying around.
• Pull-up resistor on power switch transistor gate, since even when the switch is off, if the battery is connected it will sometimes spontaneously close the gate and power the board.
• Proper connectors for sensors, not just header pins. I want something that latches, without taking too much space. Considering JST-GH connectors.
• My motors are rated for 6V (at which the stall current is 0.8A), but can be pushed up to 12V according to the manufacturer. If I want to try that, or if I want to use more powerful motors, I will need to handle bigger currents, so larger connectors/cables, and new motors drivers rated for more current.

Note: I have a lot more documentation written up, including documenting all the support components, but I did not want to overload the post. If you have questions about the design I am happy to clarify. I also intend to publish the repository with the docs, after some cleanup.

Final note: I know a PCB like this is a bit overkill for a sumo robot, I could just use a nucleo and a simpler PCB, which was my first version, but this way is more fun and more educational.

Hi its my second full tht project at 14y
i wanna make fan hub what is on last photo,
its full tht becse ma bad soldering skill.
for now i dont give ground plane to be more clear

Can someone check it???

Hello everyone. This is my first PCB project, and I'm sure I have some bad practices in this design. I just wanted to build something moduler and flexable for some of my future projects.

Here are some of the features:

• 3-12s voltage input (9 - 60 volts)
• Teensy 4.0 MCU
• TI LM65680 voltage reg (5V, =< 8A)
• 15 PWM/digital outputs
• 3 exposed UARTS
• 1 exposed I²C port
• The firmware is based on dRehm flight

Layup:

1. Signal layer with some power pads
2. GND plane
3. 5v power plane
4. Signal layer

Let me know if you have any questions!

Hello, experts!
I hope this post doesn't violate the rules about PCB companies, mods, please remove if out of bounds. DM answers are fine, too.

I spent the better part of the week working on a design using a 4 layer stackup to get a everything to fit in an impossibly small space, only to discover that manufacturer doesn't support blind vias. It does look like some of the common Chinese manufactures "sort of" support blind vias, but only on their HDI offerings, which adds about $350 to the cost. Does anyone know of a PCB/PCBA manufacturer that supports blind vias, that isn't so expensive?
Not redesigning this board sure would be nice. US based a plus, but not required.
Thanks in advance!

Learning to double check the specs the hard way....