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, 05-09-2026, 12:53 PM

**Signal Integrity Fundamentals**
From high-speed design reviews:
- Add series termination resistors (22-47Ω) on clock lines
- Separate analog/motor control grounds
- Use net labels instead of direct wiring for bus signals
([Video 8](https://www.youtube.com/watch?v=2GlWCwyEKuM&t=1044))

6. **Design for Manufacturing**
As demonstrated in PCB tutorials:
- Include test points for programming interface
- Add assembly notes for any flipped components
- Verify all component packages match distributor stock
([Video 6](https://www.youtube.com/watch?v=bcvq30J4SnQ&t=1801))

For optimal review, share:
1) PDF schematic with visible net names
2) Bill of Materials with manufacturer part numbers
3) Key component datasheets (especially motor driver & MCU)

Would you like me to elaborate on any specific aspect of these recommendations?

You can continue chatting with the AI Assistant here:
https://fedevel.com/hw-assistant

phanvanduy , 05-09-2026, 01:00 PM

"Dear Teacher, thank you for the helpful suggestions, especially regarding the decoupling capacitors and ferrite beads. I will review the videos you recommended before finalizing my schematic. I really appreciate your support for my project!”

QDrives , 05-09-2026, 07:17 PM

1) Have your schematic on a 100 mil grid.
2) Draw a transistor as a transistor, not a block.
3) Your LEDs are not going to work as connected.
4) Do not place multiple Gnd symbols on the same (connected) net.
5) Add netnames so it becomes clear what a net does.
6) Why is U4 in series with C5?

phanvanduy , 05-10-2026, 01:43 AM

"Dear Mr. QDrives,
Thank you so much for your valuable feedback on my previous schematic. I have revised the entire design based on your suggestions:
Aligned the schematic to a 100 mil grid for better clarity.
Replaced the block components with proper transistor symbols.
Fixed the LED connections; they are now connected to GPIO pins with appropriate resistors for control.
Cleaned up the Ground (GND) symbols and added clear Net Names (3.3V, LED1-3, etc.) to all connections.
Corrected the AMS1117-3.3 power circuit (the capacitors are now in parallel for proper decoupling).
Additionally, I have added a new feature: 3 Touch Button modules (TTP223) connected to GPIO pins to control the door (Up/Stop/Down).
I have attached the EasyEDA source file for your review. I look forward to hearing your thoughts. Thank you for your guidance!
Best regards,
Duy”

phanvanduy , 05-10-2026, 01:44 AM

phanvanduy , 05-10-2026, 04:01 AM

"Dear Mr. QDrives,
I just wanted to send a quick note to express my sincere gratitude for your guidance. Your detailed feedback on my schematic means a lot to me, and it has helped me learn so much more about professional design.
Thank you for being so patient and supportive of my learning journey. I truly appreciate the time and effort you spend helping students like me!
Warm regards,
Duy”
🥰

QDrives , 05-10-2026, 01:24 PM

Have you got the new schematic in PDF or screenshot too (no photo)?

phanvanduy , 05-10-2026, 01:24 PM

phanvanduy , 05-10-2026, 01:29 PM

"Hi there, I have attached the PDF and screenshots of the new schematic. Please let me know if you need anything else. Thank you!”

phanvanduy , 05-10-2026, 01:35 PM

"Dear Teacher, I would like to express my deepest gratitude for your constant care and support. Your kindness and the encouragement you have shown me mean a lot to my journey. I truly appreciate everything you have done for me. Thank you so much!”

QDrives , 05-10-2026, 07:35 PM

1) What about the transistor symbols?
2) Draw U3 with power in left and (both) outputs right. Gnd either left or right.
3) Have net labels at the MCU pins (green arrows). Best not to have pins on the top or bottom as adding net labels are more difficult to read.
4) You LEDs still not going to work
4) EN reset is shorted to Gnd.
5) Add pull-down resistors on the transistor bases.

100 mil grid is **not** for clarity, but for possible 'misconnection'. Having a wire close to a pin, but not connected. Zoomed out, you miss it.

Also note that most people here, me included, cannot read Vietnamese. But it does make things a bit more private for you.

phanvanduy , 05-10-2026, 10:11 PM

phanvanduy , 05-10-2026, 10:59 PM

"Dear Teacher QDrives,
Thank you so much for your detailed feedback on my schematic. I truly appreciate the time you spent pointing out my mistakes, especially the critical error on the EN pin and the layout of U3.
I have noted all your suggestions regarding net labels, pull-down resistors, and the grid settings. I am heading to work now and will carefully revise the entire circuit tonight once I'm back.
I look forward to sending you the updated version for further review. Thank you again for your guidance!”

Robert Feranec , 05-11-2026, 01:34 PM

I would recommend you to have a look at my ESP32 schematics or my Keyboard schematics. Try to draw it similar way. The reason why your schematic has some basic mistakes is because it is not easy to read. There are some unwritten conventions that are often used and if you follow them you will immediately spot the mistakes e.g. your LED mistakes: https://oshwlab.com/robertferanec/works

phanvanduy , 05-11-2026, 01:35 PM

phanvanduy , 05-11-2026, 02:18 PM

"Dear Teacher Robert,
I would like to express my deepest gratitude for the opportunity you have given me to learn from your courses. I feel very honored and grateful that you allowed me to study your professional designs. It is a huge motivation for me to work harder and improve my PCB design skills.
Thank you for being such an inspiring mentor. I wish you all the best!
Best regards,
Hoc Trò Duy.”

phanvanduy , 05-12-2026, 02:21 PM

"Dear Teacher Robert,
I am still trying my best every single hour. Thank you so much for giving me the opportunity to learn this knowledge that I never even dreamed I could have.
Best regards,
Hoc Tro Duy.”
🥰

phanvanduy , 05-14-2026, 02:34 PM

Subject: Updated Schematic for Review - Smart Shutter Project
"Dear Teacher QDrives,
Thank you very much for your detailed feedback on my "Smart Shutter" project. I have carefully revised the schematic based on your suggestions:
100 mil Grid: I have set the grid to 100 mil and re-checked all connections to avoid any "misconnections" or "invisible" gaps between wires and pins.
EN Pin Fix: I have corrected the error where the EN (Reset) pin was shorted to Ground.
Transistor & Pull-down: I added pull-down resistors to the transistor bases as you recommended to ensure stability.
Component Layout (U3): I have redrawn the U3 block with power input on the left and outputs on the right for better clarity.
Net Labels: I added net labels to the MCU pins and ensured they are not placed on the top or bottom to keep the schematic easy to read.
LED Circuit: I have reviewed and adjusted the LED section so it can function properly.
English Labels: I have updated all the block titles and notes to English so everyone can understand the design.
Could you please take a look at my updated version when you have time? I really appreciate your guidance and support for my learning.
Best regards,
HOC TRO DUY

phanvanduy , 05-14-2026, 02:38 PM

Subject: Thank you for your guidance & seeking your advice on my project
Dear Mr. Robert Feranec,
I am writing to express my sincere gratitude for all the tutorials and shared schematic designs you have provided. They have been an invaluable resource for me, and I have been using your designs as a foundational reference for my "Smart Shutter" project.
To be honest, I am currently at the early stages of my learning journey. While I have used your schematics to understand how to build my circuits correctly, I realize I still have a lot to learn and haven't fully developed my own original designs yet.
As I continue to work on improving my skills, I would be deeply grateful if you could share any advice on what I should focus on next to become a better designer. If you have a moment, I would also appreciate any critique or suggestions on the approach I am taking with this project.
Thank you once again for your inspiration and for sharing your knowledge with the community.
Best regards,
Hoc Tro DUY,

phanvanduy , 05-14-2026, 02:38 PM

❤️

QDrives , 05-15-2026, 10:38 AM

1) LED5 LED6 still wrong orientation
2) Gnd connection of U3 missing
3) "IO38" and "IO39" netnames do not describe what it does. Use netnames that make clear what the function is.

Robert Feranec , 05-15-2026, 11:13 AM

also, I would maybe not recommend to use 220V for this initial design - it may be too dangerous. You can use USB-C to power up your board, much safer.

phanvanduy , 05-15-2026, 01:04 PM

"Dear Robert, thank you so much for taking the time to review my design. I am truly honored and grateful for your valuable feedback, especially the safety advice regarding the use of USB-C. It means a lot to me and gives me so much motivation to keep learning. Best regards!” Hoc Tro Duy

phanvanduy , 05-15-2026, 01:08 PM

"Hi QDrives, thank you so much for your detailed feedback on my design. I've noted down the issues with LED orientation, the missing Gnd for U3, and I will definitely rename the netnames to be more descriptive. I really appreciate your help!”
Hoc Tro Duy

phanvanduy , 05-15-2026, 01:08 PM

phanvanduy , 05-15-2026, 01:09 PM

phanvanduy , 05-15-2026, 02:53 PM

"Dear Robert, I have updated my design to use USB-C for safety as you suggested. I have also been studying and applying your schematic structures to my project. May I have your permission to use your schematic concepts as a reference for my learning journey? Your guidance is a huge inspiration to me. Thank you so much!”

phanvanduy , 05-15-2026, 02:53 PM

"Hi QDrives, thank you again for your detailed feedback! I have fixed the LED orientations, connected the missing GND for U3, and renamed the nets for better clarity. I am using your advice to improve my design for learning purposes. I hope it's okay for me to follow your guidance as I practice. I truly appreciate your help!”

phanvanduy , 05-15-2026, 02:53 PM

☺️

phanvanduy , 05-17-2026, 09:55 AM

Dear Teacher Robert,
I am writing this message to express my deepest gratitude to you. Thank you so much for your inspiring courses and great guidance at FEDEVEL. Your dedication and knowledge have truly helped me find a brand new path and a huge motivation in electronics engineering. Inspired by your teachings, I am currently designing a new project: a cute smart speaker with LED lights and expressive blinking eyes! Thanks to you, I am working hard on my own projects with confidence every day.
Wishing you all the best, good health, and great success with your upcoming projects!
Sincerely,
Hoc Tro Duy

QDrives , 05-18-2026, 10:44 AM

No, you did not correct the LED orientation. You may have made it worse as now all are incorrect.
https://pcbasic.com/blog/led_polarity.html

phanvanduy , 05-18-2026, 11:26 AM

Hi QDrives,
Thank you so much for your patience and for pointing out my mistake again. I truly appreciate your guidance!
I have carefully read the article you shared about LED polarity and finally realized where I went wrong. I have updated the schematic and corrected the orientation for both the Power LED and the User LED (Anode connected to +3.3V and Cathode to GND/IO42).
I would be very grateful if you could take another look at my updated design when you have time. Thank you once again for being such a wonderful mentor!
Sincerely,
Hoc Tro Duy

phanvanduy , 05-18-2026, 11:26 AM

Robert Feranec , 05-18-2026, 12:04 PM

phanvanduy , 05-18-2026, 12:16 PM

Hi Robert,
Thank you so much for taking the time to review my schematic! Your feedback on the relay driver circuit is incredibly valuable to me.
I realized that I made a mistake with the placement of the current-limiting resistors (R15/R16) and the orientation of the flyback diodes (D1/D2). I will correct them immediately so the relay and transistors can work safely and properly.
Thank you once again for your amazing guidance and for helping me learn!
Best regards,
Hoc Tro Duy

phanvanduy , 05-18-2026, 12:16 PM

phanvanduy , 05-20-2026, 12:55 PM

Dear Mr. Robert,
I hope you are doing well.
Recently, thanks to your guidance, I have been working on the PCB design for my "Smart Shutter" project. I am currently finalizing the design and planning to manufacture a prototype to test its performance.
Since this project is very important to me, I have a strong desire to develop it into a real-world product. My goal is to eventually bring this solution to others, which would also help me support myself while pursuing my passion for engineering.
I would be very grateful if you could share your advice on how I can further develop this product. Specifically, what should I focus on to ensure the safety and reliability of the device when used in real-world conditions?
Thank you so much for your time and for all the knowledge you have shared with me.
Best regards,
Hoc Tro Duy

Robert Feranec , 05-21-2026, 02:06 PM

you need to get confidence in yourself. you can just build it and fix it and then build again. this board is simple even if something is wrong you will be be able to wire it up. if you don't feel confident, use breadboard to test the sub-circuits. I have done many videos about production, testing, product development ... you can watch them they will help: https://www.youtube.com/@RobertFeranec/search?query=product

phanvanduy , 05-21-2026, 02:18 PM

"Dear Robert,
Thank you so much for your kind words and valuable advice. I truly appreciate you taking the time to review my work. Your encouragement gives me a lot of confidence to keep going.
I will follow your advice, start testing the sub-circuits, and keep building, fixing, and improving. I’m really excited to turn this project into something great. I’ll definitely check out your videos on product development as you suggested.
Thank you once again for your mentorship!
Best regards,
Hoc Tro Duy

phanvanduy , 05-21-2026, 02:18 PM

phanvanduy , 05-25-2026, 01:47 PM

"Dear Robert, thank you once again for your mentorship. I'm learning a lot from your guidance. One day, I hope to have the honor of taking a photo with you at the SMT factory. It would be a dream come true!"
Học Trò Duy🥰

phanvanduy , 05-25-2026, 01:53 PM

"Dear Robert, thank you again for your continued support. I have a new idea for my project: I would like to integrate a surveillance camera into the system to enhance its smart home capabilities. Could you please share your advice on this? Also, may I have your permission and guidance to pursue this development? One day, I hope to have the honor of taking a photo with you at the SMT factory. Thank you so much for your mentorship!"
Học Trò Duy

phanvanduy , 05-31-2026, 03:13 AM

"Dear Robert,
I hope you are having a great day.
I am Hoc Tro Duy, and I have been following your tutorials to work on my own PCB project for a smart shutter system. I have successfully designed the schematic and have been working on the layout. However, I have reached a point where I am struggling with the routing and the overall board arrangement, and I am unsure how to proceed to the next level.
I would be very grateful if you could take a look at my current progress and provide some feedback or advice on how to optimize this 2-layer design.
Thank you so much for your time and for all the knowledge you share.

phanvanduy , 05-31-2026, 05:17 AM

"Dear Robert,
I hope this email finds you well.
Following our previous interaction, I have been reflecting on the future of my smart shutter project. I have decided to approach this as a limited-edition development, focusing on a small number of units. My intention is to learn and grow through this process while strictly ensuring that my work remains independent and does not interfere with or negatively impact the core technology or its originators.
I would highly value your guidance on this path. If you could share your perspective on how to maintain this balance—developing my own small-scale solutions while staying respectful to the existing technology—I would be truly grateful.
Thank you for being such an inspiration to me.
Best regards,
Học Trò Duy 🥰

QDrives , 05-31-2026, 01:09 PM

1) For review it is better to keep colors **per layer**.
2) Have the D+ and D- side by side.
3) Make it a 4 layer board.
4) Keep the diode (D1) close to the relay.

phanvanduy , 05-31-2026, 01:09 PM

phanvanduy , 06-01-2026, 12:11 AM

"Dear Mr. QDrives,
Thank you so much for your valuable advice. Your guidance has been incredibly helpful and has truly helped me solve the challenges I was facing with my project. I sincerely appreciate your time and support!
Best regards,
Học trò Duy"

phanvanduy , 06-06-2026, 11:08 AM

phanvanduy , 06-06-2026, 11:12 AM

"Dear Mr. Robert,
I am happy to share that I have completed my 'Smart Shutter Control System' project. While there is still room for improvement, this project serves as a solid foundation for my future development as an engineer. I would like to express my deepest gratitude to you; your patience and invaluable guidance have been a great inspiration that helped me overcome all the challenges. Thank you once again for all your support along the way.
Best regards,
Học Trò Duy"

phanvanduy , 06-06-2026, 11:14 AM

"Dear Mr. QDrives,
I am happy to share that I have completed my 'Smart Shutter Control System' project. While there is still room for improvement, this project serves as a solid foundation for my future development as an engineer. I would like to express my deepest gratitude for all the invaluable knowledge you have taught me. Your patience and guidance have been a great inspiration, helping me overcome all the challenges during the design process. Thank you once again for all your support.
Best regards,
Học Trò Duy"