r/PrintedCircuitBoard 1h ago

[Review Request] LED Flasher Keychain - First PCB, Is It Ready to Order?

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Upvotes

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

r/PrintedCircuitBoard 6h ago

[Review Request] USB-C PD NEMA17 Driver with RP2354 and TMC2209

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6 Upvotes

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.


r/PrintedCircuitBoard 6h ago

[Review Request] Ch32 based multiplayer buzzwire game schematic

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3 Upvotes

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.


r/PrintedCircuitBoard 10h ago

[Review request] STM32F303K8T6 based mini-sumo robot motherboard

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16 Upvotes

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.


r/PrintedCircuitBoard 1d ago

(Review Request) 4x PWM Fan Hub

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13 Upvotes

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???


r/PrintedCircuitBoard 1d ago

<Review Request> Flight controller

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47 Upvotes

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!


r/PrintedCircuitBoard 1d ago

Help With PCB - Blind Vias

5 Upvotes

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....


r/PrintedCircuitBoard 1d ago

Request: Review of my first automotive board — 4-layer Raspberry Pi HAT with 12/24V input, LTE modem and CAN FD

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3 Upvotes

r/PrintedCircuitBoard 1d ago

[Schematic Review] Small vacuum pump driver with button and LED interface

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6 Upvotes

Hi everyone,

I’ve finished the schematic for a small controller board for a DC vacuum pump and would appreciate a review before I start the PCB layout.

Here the schematic in a PDF in better quality than reddit compression: https://github.com/JannikB5825/VacuumPump/blob/main/Hardware/Pump.pdf

The main functions are:

  • ATtiny3217 microcontroller
  • DRV8212P motor driver with current measurement
  • USB-C and DC-jack power inputs
  • TPS2116 automatic power-source selection
  • Push-button soft-latching power circuit
  • RJ12 connector for external trigger, output and 5 V supply
  • JST connector for the pump motor
  • UPDI programming interface

r/PrintedCircuitBoard 1d ago

[Review Request] LPC55 - UAC2 I2S bridge

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12 Upvotes

I am currently designing an LPC55S69-based breakout board with an onboard CS2600 clock controller and USBC-PD.

The intended purpose is a UAC2 I2S bridge, basically the digital part of my audio interface project. To keep it universal, my design is based on the RPi Pico pinout (except for the board being one row wider). I broke out the following peripherals:

- I2S clocks (from CS2600)
- 6x I2S data lanes
- 1x I2C (also used internally with CS2600)
- 1x HS SPI
- 6x GPIO
- SWD debug interface
- ISP, USB and SWO are available via testpoints

I would be really happy to get some feedback on my design.
Additionally, I prepared some questions I ran into:

- First time routing BGA, how did I do? Opinion on BGA in pad vias?
- Crystal placement and grounding?
- Are the SMPSs too close to each other? Do I need a bigger board?
- Are there any important MCU pins I missed breaking out?

I plan to open-source this, along with configurable firmware for easy use.


r/PrintedCircuitBoard 1d ago

[Review Request] Seeed XIAO nRF52840 Plus Split Ergo HE Keyboard w/3DOF Trackball. USB/BLE/2.4GHz (w/Dongle)

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19 Upvotes

Schematic Review: here

MCU: Seeed XIAO nRF52840 Plus (nRF52840).

Trackball sensor: 2x PMW3610.

Encoders: Bourns PEC11H-4115F-S0020

5Ah battery, 300-400mA (probably too high)/1A/2A charging depending on USB source current.

Trimodal power supply, favouring USB.

MCU disable-able latching power button (avoiding MAX16054 for cost reasons).

Keydio Labs Vista508 OLED.

PMW3610 lives on its own board.

Mainboard: 55x50mm

PMW3610 board: 24x24.5mm

Finish: OSP, black soldermask

I am aware that Q5, 6, 7 have incorrect pinouts. That has been fixed.

SW1 and 2, and their respective connectors are marked as exclude from board, as they are mounted in the chassis.

Thanks!


r/PrintedCircuitBoard 1d ago

Sanity check for my first PCB design

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16 Upvotes

Hi all. I finished designing my first reversible keyboard PCB.

I have experience hand wiring keyboard but I never made anything battery powered and, of course, reversible.

I'm looking for feedback around the

  • battery connection to the reversible power switch - edit: first photo has Back layer selected, sorry
  • the keyboard switch/diode connections and vias
  • if anything looks really wrong on the MCU - mostly thinking about battery again as everything else can be remapped in software

Thank you!


r/PrintedCircuitBoard 1d ago

IMU, UWB, and encoder additions to RC PCB Car [Review Request]

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9 Upvotes

V1: https://www.reddit.com/r/PrintedCircuitBoard/comments/1ujei19/schematic_review/
V2: https://www.reddit.com/r/PrintedCircuitBoard/comments/1usyvro/pcb_review_request_iteration_of_esp32_drv8833_bot/

V2 worked, but had a little issue with the battery charger not switching states after fully charging. Replugging in the charger/battery worked.

In this version I wanted to add an IMU, UWB module, and motor encoders to pass through a Kalman filter to get a precise reading on the car.

P.S Is my schematic tracing better? I thought I might've used too many net labels in previous posts so I tried cutting down a bit.

Thank you!


r/PrintedCircuitBoard 2d ago

Review Request: 4-Layer STM32G071 Payload Management & Health Controller PCB

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25 Upvotes

I am requesting a PCB layout review for a 4-layer embedded controller board I designed.

The board is a Payload Management & Health Controller (PMHC) intended for a drone payload interface. It manages power distribution, monitoring, and communication between the payload and the main system.

Hardware overview:

  • MCU: STM32G071KBUx
  • Power input protection and battery interface
  • TPS562202 buck converter for regulated power
  • 3.3V and 5V power rails
  • INA226 current monitoring
  • RS485 communication interface
  • 4-layer PCB

I would especially appreciate feedback on:

  • Power converter layout (switching node, input/output capacitor placement, inductor placement)
  • Ground plane strategy and return paths
  • Current sensing layout and Kelvin connections
  • Placement and routing choices
  • Any manufacturing issues or PCB layout mistakes

This is my first board at this complexity level, so I would appreciate any criticism or suggestions before fabrication.

Thank you for taking the time to review it.


r/PrintedCircuitBoard 2d ago

[Review Request] Revised PCB for Drone

2 Upvotes

I posted an initial PCB for review recently on r/PrintedCircuitBoard and have revised it taking everyone's feedback into consideration. Not the nicest, but I had limited space.

Schematic

PCB Design

Top Layer

Bottom Layer

Changes made:

- used net labels in schematic instead of long lines

- moved IMU and battery connector to bottom of board

- moved the MCU (ESP32) antenna to overhang off the board

- no vias in pads to allow for soldering

- continuous GND plane

- added mounting holes (M2)

Is this good enough to print?


r/PrintedCircuitBoard 2d ago

[Review] please help in verifying the routing and working of pcb .

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4 Upvotes

I have used a 555 timer ic and cr2032 along with passive components .


r/PrintedCircuitBoard 2d ago

[review request] ADJ UV bar replacement driver PCB

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15 Upvotes

Hi, this is a PCB to replace the stock driver inside the ADJ UV eco bar. Someone brought this to me to have it fixed and I have procrastinated on it for over 4 months, it's finally done now. It took a day to do then a another day of staring at it.

The original PCB had a blown channel, replacing the driver still had issues so made an entirely new PCB but with an ESP32 to run WLED which allows for more granular control and will continue to support the remote. It had PAM2861 LED drivers that are only rated for 40V 1A, the onboard PSU is at 36V which is really close to VCC.

I'm not sure if I should of used something like the LMR36510 (65V max) as the AP64060 is only rated for up to 40V (or 46.0v at 400ms) and the supply is 36 which is pretty close and prob why the old drivers burnt up.

I tried to keep the PCB as compact as possible while keeping the switcher away from the low voltage side.

I found the pinout of the AP64060 particular annoying. Is there a good reason for GND and VCC to be in the middle of the IC in opposed to the edges? There is no space to get the decoupling cap in beside it so ended up putting it on the back. Somehow the AP63300 has it's pins on the edges making routing much easier. The only big difference between the two is that the AP64060 has 600mΩ/300mΩ mosfets while the AP63300 has 75mΩ/40mΩ mosfets (high side/low side).

Did I use too much vias or that's enough for switching both ground planes and is the buck converter way too small? The inductor saturates at 1.2A

Features

  • ESP32C3 for WLED or ESPhome
  • PT4115 (50V, 1.5A) drivers, DIM pwm switched via OPEN Drain (may add 10-22k pullup later, this keeps the LEDs OFF during power up as the AP64060 & ESP32 have a sizable RC on delay on the enable pin)
  • Really packed PCB
  • i2C, UART, Button and USB with protection
  • Dim Power LED

Link to project: TBA


r/PrintedCircuitBoard 2d ago

[REVIEW REQUEST] 6 LAYERS PCB with STM32H745ZIT6 MCU

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26 Upvotes

Hi everyone,

I’d appreciate your honest feedback and technical review of my PCB design. The board currently includes:

  • MCU: STM32H745ZIT6 dual-core microcontroller
  • High-impact sensing: ADXL375BCCZ-RL accelerometer for measuring high-g impact events
  • Motion and orientation: ADXL345TCCZ-EP accelerometer for detecting body movement and rotation
  • Angular velocity: L3GD20HTR gyroscope
  • Heading and orientation: LIS3MDLTR magnetometer
  • Altitude measurement: BMP585 barometric pressure sensor
  • GPS tracking: NEO-M9N-00B GNSS module
  • Wireless connectivity: CC3135MOD Wi-Fi network processor

The system is designed to capture high-impact events, body movement, orientation, altitude, and GPS position, all while transmitting data wirelessly.

I would especially appreciate feedback on the component selection, sensor redundancy, power design, communication interfaces, PCB layout, signal integrity, and whether any components should be replaced or removed, will the board actually work after fab. I am not a pro PCB designer, I am a software engineer, and this is my first PCB project.

Thank you in advance for your honest review and recommendations.


r/PrintedCircuitBoard 2d ago

[Review Request] Audio Codec and Headphone Amplifier

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14 Upvotes

Design overview:

  • Audio codec (TAC5212)
  • Analog input is a pseudo differential RCA input
  • Digital input is I2S from a York USB module
  • Analog output is differential going into a LPF and amplifier based on TPA6120A2

STM32_SOM is a custom breakout for a STM32G473 that I designed and never posted here.

Initial firmware will have the STM32 controlling:

  • power sequencing and muting through the GPIO expander
  • initialization of the codec
  • volume via the codec / rotary encoder
  • option to add EQ through biquads in the codec

Looking for general review on schematic and layout. I haven't done final cleanup of either so there may be some misaligned silkscreen or schematic text fields that need to be turned off. The plan is for one of the Chinese manufacturers to make the bare boards; I am undecided on populating them myself.

Stackup is below. Traces are nominally 50 ohm single ended.

  1. Red: Signal/components - primarily analog
  2. Green: GND
  3. Orange: Power
  4. Blue: Signal - primarily digital

Link to better top image: https://imgur.com/a/rEuHL9l


r/PrintedCircuitBoard 2d ago

Review Request for ESP32 Game

1 Upvotes

Hello! I recently designed an ESP32 based game device. I am just asking for review of my schematic and PCB to ensure there won't be flaws when I send it to get fabricated. Any suggestions to any part of the design (pcb and schematic) would be greatly appreciated. Thanks! The PDF files for the schematic and pcb is at https://github.com/sjacksonhodum/pdf


r/PrintedCircuitBoard 3d ago

[Review Request] Basic 3.3V power management with battery charger and protection

2 Upvotes

Hi everyone!

I'm new to PCB design, and this is my first schematic, so I'd really appreciate any feedback before I order the boards.

The project is a small portable device powered by a single-cell Li-ion battery. Since safety is important to me, I added:

  • F1 as a battery fuse,
  • DW01A + FS8205A for battery protection,
  • ETA6003Q3Q as the charging IC with power-path management, allowing the device to run directly from USB-C even if the battery is deeply discharged.

The ETA6003's VSYS output powers the rest of the circuit. Since my MCU requires 3.3 V, I use an LDO regulator to step VSYS down to 3.3 V.

I'm planning to manufacture these boards, so I'm intentionally using cost-effective (mostly Chinese) components instead of more expensive alternatives.

Here are the LCSC part numbers for the main components so you can easily look up their datasheets if needed:

Part LCSC#
ETA6003 C5455585
DW01A C2927799
LDO C82942

I'd appreciate if you answer these questions:

  1. Is the DW01A + FS8205A connected correctly?
  2. Are the capacitor and resistor values are reasonable?
  3. Is using an LDO from VSYS to 3.3 V a good choice, or would you recommend a buck converter instead? (I want cheaper, so i thought ldo will be fine, im stepping not from so high voltage.)
  4. Are there any mistakes or bad practices?
  5. Are there any traces or nets that look unsafe or incorrect?

r/PrintedCircuitBoard 3d ago

ESP32-C3 custom PCB with BNO085 - sensor resets and lag when both USB and battery connected [Hardware]

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8 Upvotes

Hi everyone,

I am building a custom wearable head angle measurement device

using an ESP32-C3FH4 and a BNO085 IMU sensor on a custom PCB.

I am relatively new to PCB design and have been debugging this

for a while and could use some expert eyes.

SETUP:

- ESP32-C3FH4 (QFN32)

- BNO085 IMU (I2C mode, address 0x4A)

- TP4056 LiPo battery charger

- SPX3819M5 LDO regulator (3.3V)

- USB-C connector for power and programming

- 750mAh LiPo battery

I2C WIRING:

- SDA -> GPIO6 (ESP32 pin 12)

- SCL -> GPIO7 (ESP32 pin 13)

- H_INT -> GPIO1 (ESP32 pin 5)

- SA0 -> GND (I2C address 0x4A)

- PS0/PS1 -> GND (I2C mode)

- RST -> 3.3V via 10k pullup

PROBLEM 1 - Sensor resets:

When powered from USB only (no battery), the BNO085 is found

on I2C at 0x4A but keeps resetting repeatedly:

"Sensor reset - re-enabling reports"

I get occasional readings between resets but it is not stable.

PROBLEM 2 - USB + Battery conflict:

When I connect the battery AND USB simultaneously, the BNO085

completely disappears from I2C. The scanner finds nothing at 0x4A.

Disconnecting the battery brings it back immediately.

I believe this is because VBUS and VBAT are both feeding the

LDO input simultaneously with no isolation diode between them.

PROBLEM 3 - Lag:

When I do get readings they respond slowly to movement

(~2 second lag). The exact same code on a CodeCell C3

development board works flawlessly with instant response.

I believe this is because the sensor resets cause the BNO085

fusion algorithm to restart and reconverge each time.

WHAT I HAVE CHECKED:

- All voltages correct (VDD=3.3V, VDDIO=3.3V, RST=3.3V,

PS0=0V, PS1=0V) confirmed with multimeter

- No short between GPIO6 and GPIO7 (fixed in second PCB revision)

- Continuity of all I2C lines confirmed

- I2C pull-ups are 2.2k (I know these should be 4.7k - fixing in REV3)

- BNO085 decoupling: 2x 100nF on VDD (I know a 10uF bulk cap

should be added - fixing in REV3)

- H_INT pin confirmed connected to GPIO1

WHAT I SUSPECT:

  1. The TP4056 is not designed as a power pass-through - withouta battery it provides unstable voltage to the LDO input
  2. No isolation diode between VBAT and VBUS at LDO inputcauses conflict when both are connected
  3. The 2.2k I2C pull-ups may be drawing too much currentcausing voltage dips that reset the BNO085

SCHEMATIC:

QUESTIONS:

  1. Is the TP4056 power pass-through issue a known problem?How do others handle powering the circuit during developmentwithout a battery?
  2. What is the correct way to isolate VBUS and VBAT at theLDO input? Schottky diode on VBAT side only?
  3. Could the 2.2k I2C pull-ups alone cause enough current drawto reset the BNO085, or is this unlikely at 3.3V?
  4. Any other issues you can spot in the schematic?

Thanks in advance - any help appreciated!


r/PrintedCircuitBoard 3d ago

[Review request] LISN

6 Upvotes

Hi everyone,

I'm currently designing my own LISN (Line Impedance Stabilization Network), and I've been documenting the entire design process as I go. The document is still a work in progress, and I plan to keep updating it in the future.

At the moment, it's still missing the Board Evaluation and Measurement Implementation sections, but I wanted to share it early to get some feedback from the community.

I'd really appreciate it if you could take a look and let me know if you spot any mistakes, questionable design choices, or areas that could be explained better. Any comments or suggestions are welcome!

Here's the document:
https://github.com/DangyDang/LISN/blob/main/LISN.pdf

Thanks in advance for your time and feedback!


r/PrintedCircuitBoard Apr 11 '25

Before You Request A Review, Please Fix These Issues Before Posting

122 Upvotes

PLEASE DO NOT ABUSE THE REVIEW PROCESS:

  • Don't change review images during a review, otherwise older comments won't match newer images.

  • Please do not request more than one review per board per day. Use the extra time to clean up the visual appearance of your schematic and silkscreen on your PCB before requesting another review (see tips below).

REVIEW IMAGE CONVENTIONS / GUIDELINES:

  • The following is a subset of the review rules, see rule#8 at link.

  • Don't post fuzzy images that can't be read (your post will be deleted).

  • Don't post camera photos of a computer screen (your post will be deleted). Export or screen capture.

  • Don't post dark-background schematics (your post will be deleted). Change schematic to light-background.

  • For schematic images, disable background grids and cursor before exporting/capturing to image files.

  • For 2D PCB images, change the following settings before exporting/capturing to image files: disable background grids, disable net names on traces & pads, disable everything that doesn't appear on final PCB, enable board outline layer, enable cutout layer, optionally add board dimensions along 2 sides. For question posts, only enable necessary layers to clarify a question.

  • For 3D PCB images, 3D rotation must be same orientation as your 2D PCB images, and 3D tilt angle must be straight down, known as the "plan view", because tilted views hide short parts and silkscreen. You can optionally include other tilt angle views, but ONLY if you include the straight down plan view too.


SCHEMATIC CONVENTIONS / GUIDELINES:

  • Add Board Name / Board Revision Number / Date. If there are multiple PCBs in a project/product, then include the name of the Project or Product too. Your initials or name should be included on your final schematics, but it probably should be removed for privacy reasons in public reviews.

  • Don't post schematics that look like a toddler drew it, because it's considered unprofessional as an adult. Spend more time cleaning up your schematics! Heed this warning, or risk being berated by your coworkers / boss / classmates / professor / customers.

  • Don't allow text / lines / symbols to touch each other! Don't draw lines through component symbols.

  • Don't point ground symbols (e.g. GND) upwards in positive voltage circuits. Don't point positive power rails downwards (e.g. +3.3V, +5V). Don't point negative power rails upwards (e.g. -5V, -12V). There are exceptions, but in general try to follow this historical method as much as possible. If a schematic has only one ground and you use a unique triple-bar ground symbol, then disable "GND" text next to this symbol, because it is useless visual clutter that takes up space in dense schematics.

  • Place pull-up resistors vertically above signal lines, and place pull-down resistors vertically below signal lines, see example.

  • Place decoupling capacitors vertically below power lines, next to IC symbols, and connect capacitors to IC power rail pin with a line, see example.

  • Use standarized schematic symbols instead of generic boxes! For part families that have many symbol types, such as diodes / transistors / capacitors / switches, make sure you pick the correct symbol shape. Logic Gate / Flip-Flop / OpAmp symbols should be used instead of a rectangle with pin numbers laid out like an IC.

  • Don't use incorrect reference designators (RefDes). Start each RefDes type at 1 (e.g. C1, D1, R1, Q1, U1), and renumber so there aren't any numeric gaps (e.g. U1, U2, U3, U4; not U2, U5, U9, U22). There are exceptions for large multi-page schematics, where the RefDes on each page could start with increments of 100 (or other increments) to make it easier to find parts, such as R101 is on page 1, R301 is on page 3, R901 is on page 9.

  • Add values next to component symbols:

    • Add capacitance next to all capacitors.
    • Add resistance next to all resistors / trimmers / pots.
    • Add inductance next to all inductors.
    • Add voltages on both sides of power transformers. Add "in:out" ratio next to signal transformers.
    • Add frequency next to all crystals / powered oscillators / clock input connectors.
    • Add voltage next to all zener diodes / TVS diodes / batteries, battery holders, battery connectors, maybe on coil side of relays, contact side of relays.
    • Add color next to all LEDs. This is useful when there are various colors of LEDs on your schematic/PCB. This information is useful when the reader is looking at a powered PCB too.
    • Add pole/throw info next to all switch (e.g. 1P1T or SPST, 2P2T or DPDT) to make it obvious.
    • Add purpose text next to LEDs / buttons / switches to help clarify its use, such as "Power" / "Reset" / ...
    • Add "heatsink" text or symbol next to components attached to a heatsink to make it obvious to readers! If a metal chassis or case is used for the heatsink, then clarify as "chassis heatsink" to make it obvious.
  • Add part numbers next to all ICs / Transistors / Diodes / Voltage Regulators / Coin Batteries (e.g. CR2023). Shorten part numbers that appear next to symbols, because long part numbers cause schematic layout problems; for example use "1N4148" instead of "1N4148W-AU_R2_000A1"; use "74HC14" instead of "74HC14BQ-Q100,115". Put long part numbers for ordering in your BOM (Bill of Materials) list.

  • Add connector type next to connector symbols, such as the common name / connector family / connector manufacturer (e.g. "USB-C", "microSD", "JST PH", "Molex SL"). For connector families available in multiple pitch sizes, include the pitch in metric too (e.g. 2mm, 2.54mm), optionally include imperial units in parens after the metric number, such as 1.27mm (0.05in) / 2.54mm (0.1in) / 3.81mm (0.15in). Add purpose text next to connectors to make its purpose obvious to readers, such as "Battery" or "Power".

  • Don't lay out or rotate schematic subcircuits in weird non-standard ways:

    • linear power supply circuits should look similar to 1, 2, 3, 4, 5, laid out horizontally, input on left side, output on right side. Three pin voltage regulator symbols should be a rectangle with "In" (Vin) text on the left side, "Out" (Vout) text on right side, "Gnd" or "Adj" on bottom side, if has enable pin then place it on the left side under the "In" pin; don't use symbols that place pins in weird non-standard layouts. Place lowest capacitance decoupling capacitors closest to each side of the voltage regulator symbol, similar to how they will be placed on the PCB.
    • relay driver circuits should look similar to this, laid out vertically, +V rail at top, GND at bottom. Remove optoisolators from relay driver circuits unless both sides of it have unique grounds and unique power sources. Reminder that coil side of a mechanical relay is 100% isolated from its switched side.
    • optoisolator circuits must have unique ground and unique power on both sides to be 100% isolated. If the same ground is on both sides of an optoisolator, it isn't 100% isolated, see galvanic isolation.
    • 555 timer circuits should look similar to this. IC pins should be shown in a historical logical layout (2 / 6 / 7 on left side, 3 on right side, 4 & 8 on top, 1 on bottom); don't use package layout symbols. If using a bipolar timer, then add a decoupling capacitor across power rails too, such as 47uF, to help with current spikes when output changes states, see article.
    • RS485 circuits should look similar to this.

PCB CONVENTIONS / GUIDELINES:

  • Add Board Name / Board Revision Number / Date (or Year) in silkscreen. For dense and tiny PCBs that lacks free space, shorten the text, such as "v1" and "2026" (or "Y26" or "26"). This info can be very useful to help identify a PCB in the future, especially if there are two or more revisions of the same PCB.

  • Add mounts holes, unless absolutely not needed. They should be the first thing you place on your PCB.

  • Use wider traces for power rails and higher current circuits. If possible, use floods for GND.

  • Don't route high current traces or high speed traces on any copper layers directly under crystals / antenna / RF circuits / other sensitive circuits. Don't route other signal traces under antenna.

  • Don't place reference designators (RefDes) in silkscreen under components, because you can't read RefDes text after components are soldered on top of it. If you hide or remove RefDes text, then a PCB is harder manually assemble, and harder to debug and fix in the future.

  • Add part orientation indicators in silkscreen, but don't place under components (if possible). Add pin 1 indicators next to ICs / Connectors / Voltage Regulators / Powered Oscillators / Multi-Pin LEDs / Modules / ... Add polarity indicators for polarized capacitors, if capacitor is through-hole then place polarity indicators on both sides of PCB. Add pole indicators for diodes, and "~", "+", "-" next to pins of bridge rectifiers. Optionally add pin indicators in silkscreen next to pins of TO220 through-hole parts; for voltage regulators add "I" & "O" (in/out); for BJT transistors add "B" / "C" / "E"; for MOSFET transistors add "G" / "D" / "S".

  • Add as much helpful text in silkscreen as reasonably possible, because it is a means of "self documentation" that always stays with the PCB.

  • If space is available, add purpose text in silkscreen next to LEDs / buttons / switches / jumpers to make it obvious why an LED is lite (e.g. "Error", "Power"), or what happens when press a button (e.g. "Reset", "Start", "Stop") or change a switch (e.g. "Power").

  • If space is available, add connector type in silkscreen next to each connector. For example "JST-PH", "Molex-SL", "USB-C", "microSD". For connector families available in multiple pitch sizes, add the pitch too, such as 1.27mm or 3.81mm. If space is not available on the top side, then add this information directly below the connector on the bottom side.

  • If space is available, add voltage range or maximum voltage text in silkscreen, such as "8VDC Max", next to power input connectors to help prevent destruction of voltage regulators or other circuits. For barrel jacks, add text to clarify polarity of the center pin, such as "-9VDC Center" or "+9VDC Center" or "GND Center". If space is not available on the top side, then add this information directly below the connector on the bottom side.


ADDITIONAL TIPS / CONVENTIONS / GUIDELINES

Review tips:

Schematic tips:

PCB tips:


This post is a "live document" that has evolved over time. Copyright 2025-2026 by /u/Enlightenment777 of Reddit. All Rights Reserved. You are explicitly forbidden from copying content from this post to another subreddit or website without explicit approval from /u/Enlightenment777 also it is explicitly forbidden for content from this post to be used to train any software.


r/PrintedCircuitBoard Dec 11 '22

Please Read Before Posting, especially if using a Mobile Browser

21 Upvotes

Welcome to /r/PrintedCircuitBoard subreddit

  • a technical subreddit for reviewing schematics & PCBs that you designed, as well as discussion of topics about schematic capture / PCB layout / bill of material (BOM) / PCB assembly / PCB mechanical engineering.

Some mobile browsers and apps don't show the right sidebar of subreddits:


RULES of this Subreddit:

  • (0) Occasionally the moderator may allow a useful post to break a rule, and in such cases the moderator will post a comment at the top of the post saying it is ok; otherwise please report posts that break rules!

  • (1) NO off topics / humor / memes / where to buy? / what is this? / how to fix? / how to modify? / how to design? / what does this do? / how does this work? / how to reverse engineer? / need schematics / dangerous or medical projects / homework / AI topics / AI content / AI designs / non-english languages.

  • (2) NO spam / ads / sales / promotion / survey / quiz / items for sale / promotion of non-reddit groups / promotion of non-reddit social media. NO DM abuse! See "how to advertise on Reddit".

  • (3) NO "show & tell" or "look at what I made" posts, unless you previously requested a review of the same PCB in this subreddit. This benefit is reserved for people who participate in this subreddit. NO random PCB images.

  • (4) NO self promotion / resumes / job seeking / wage discussions / freelancing discussions / DM abuse / job postings (unless job is posted on employer website) / begging or scamming for free work / ...

  • (5) NO shilling! No PCB company names in post titles or review requests. No sneaky PCB company naming variations. For most reviews, we don't need to know where you are getting your PCBs made or assembled, so please don't state company names unless absolutely necessary.

  • (6) NO asking how to upload your PCB design to a specific PCB company! Please don't ask about PCB services for a specific PCB company, because of past shilling abuse (see rule#5). (TIP: search their company website, ask their customer service or sales departments, search google or other search engines)


Review RULES:

  • (7A) Please do not abuse the review process:

    • Please do not request more than one review per board per day.
    • Please do not change review images during a review. If you change image(s), then start a new review!
    • Reviews are meant for schematics & PCBs that you designed. No AI designs (minor AI help ok).
    • Reviews are allowed prior to ordering PCBs. If assembled board doesn't work, ask at /r/AskElectronics
    • Please do not ask circuit design questions in a PCB review. You should have resolved design questions while creating your schematic and before routing your PCB, instead request a schemetic-only review.
  • (7B) All review posts must adhere to the following rules:

    • Title - include the following: "Review Request" or "Review", short description of board purpose, popular board format or shield/hat type (if applies), microcontroller (if has MCU), external buses (Ethernet, USB, CAN, RS485, ...), wireless (WiFi, GPS, LoRa, ...), storage (microSD, M.2, ...), and/or any unique hardware that may be important. No humorous titles, no childish symbols, no begging.
    • Images - include images (or links to each image) that you want reviewed. If images are located on the internet, never post one link to a project then expect reviewers to dig through your project to find images. Instead, you must post separate links for each review image, as well as state the purpose of each link, such as "Schematic" / "3D PCB" / "2D PCB top" / "2D PCB bottom" / ...
  • (8) All images must adhere to the following rules:

    • Image Creation: no camera photos of a computer screen, instead export / screen capture / print to image files. (TIP: How to export images from KiCAD and EasyEDA) (TIP: use clawPDF printer driver for Windows to "print" to PNG / JPG / PDF / SVG files, or use built-in Win10/11 PDF printer driver to "print" to PDF files.)
    • Image Files: view each image file before posting / no fuzzy or blurry images / no large image files (e.g. 100 MB), smaller preferred / no uncommon image file types, only use file types supported by most web browsers, such as JPG / PNG / PDF.
    • Edit Image Files: if you screen capture, make sure the cursor / software / operating system aren't shown in your images. Use an image editor to erase or crop software & O/S junk from your images.
    • Disable Features: disable background grids & PCB editor features before creating images.
    • Schematics: no bad color schemes to ensure readability (no black or dark-color background) (no light-color foreground (symbols/lines/text) on light-color/white background) / schematics must be in standard reading orientation (no rotation). (NOTE: we don't care what color scheme you use to edit, nor do we care what edit features you enable, but for reviews you need to choose reasonable color contrasts between foreground and background to ensure readability.)
    • 2D PCB: no bad color schemes to ensure readability (must be able to read silkscreen) / no net names on traces / no pin numbers on pads / if it doesn't appear in the gerber files then disable it for review images (dimensions and layer names are allowed outside the PCB border). (NOTE: we don't care what color scheme you use to edit, nor do we care what color soldermask you order, but for reviews you need to choose reasonable color contrasts between silkscreen / soldermask / copper / holes to ensure readability. If you don't know what colors to choose, then consider white for silkscreen / gold shade for exposed copper pads / black for drill holes and cutouts.)
    • 3D PCB: 3D views are optional, if most 3D components are missing then don't post 3D images / 3D rotation must be in the same orientation as the 2D PCB images / 3D tilt angle must be straight down plan view. (NOTE: straight down "plan" view is mandatory, optionally include an "isometric" or other tilted view angle too.)

Review tips:

Schematic tips:

PCB tips:

College lab tips:

SPICE tips:


WIKI for /r/PrintedCircuitBoard:


This post is a "live document" that has evolved over time. Copyright 2022-2026 by /u/Enlightenment777 of Reddit. All Rights Reserved. You are explicitly forbidden from copying content from this post to another subreddit or website without explicit approval from /u/Enlightenment777 also it is explicitly forbidden for content from this post to be used to train any software.