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Associate
November 28, 2025
Question

draft for donut board (aka "pad" or "matrix" board)

  • November 28, 2025
  • 3 replies
  • 396 views

Title edited to clarify "donut board"


IMG_4839.pngI would like to connect the LM324(below) to the STM32F103C8T6 on a donut board, purpose to read four IR receivers. VR with highlight T shape is preset 103. IR1, IR2, IR3, IR4, 5V and ground will connect to a 6 pin header, connect to another donut board which contains only 4 groups of IR transmitters and receivers.

My task is without jumper wires connect them together but I can’t connect it due to the preset 103 make the circuit too messy. Can anyone help me please.:folded_hands:

3 replies

AScha.3
Super User
November 28, 2025

Not clear, what you want to build : IR receivers - which one ? type, name , ds ...

+

for IR remote - or what ?

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ziminAuthor
Associate
November 28, 2025

image.jpg

I think that is not important, I’m new on this, I want to build a follow line autocar, these will be the sensors.

image.jpg

image.jpg
These two pictures are two drafts of donut board. I want to connect the circuit on donut board without using jumper wires. Others I have already connected. Only the LM324(circle with red pen) I can’t connect due to too many preset 103 need to connect with 5V and GND and there is no way to connect “input+” on LM324

Andrew Neil
Super User
November 28, 2025

@zimin wrote:

a donut board


A what ?

 

Also unclear what you're trying to achieve, and where you're stuck?

Do you have a schematic (aka "circuit diagram") of what you're trying to build?

It would help if you posted the images in correct orientation so they're easier to read.

 

Remember that we know absolutely nothing about you or your project - so you need to explain things clearly & completely.

 

How to write your question to maximize your chances to find a solution

 

PS:

When you say "donut board", do you mean something like this?

AndrewNeil_1-1764345031937.png

A complex system that works is invariably found to have evolved from a simple system that worked.A complex system designed from scratch never works and cannot be patched up to make it work.
mƎALLEm
Technical Moderator
November 28, 2025

@Andrew Neil wrote:

When you say "donut board", do you mean something like this?

AndrewNeil_1-1764345031937.png


I think it's the case:

https://qqtrading.com.my/stripboard-9-x-15cm-donut-board 

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Andrew Neil
Super User
November 28, 2025

@mƎALLEm wrote:


I think it's the case:


Thanks.

More commonly known as "matrix board" or "pad board".

 

@zimin In that case, I don't understand what you mean by, "without using jumper wires" ?

All of the pads are isolated on this type of prototyping board - so the only way to build a circuit is with "jumper" wires to connect things together!

Here's one I'm using at this very moment:

AndrewNeil_2-1764348114848.png AndrewNeil_3-1764348139929.png

 

PS:

Some more examples here.

A complex system that works is invariably found to have evolved from a simple system that worked.A complex system designed from scratch never works and cannot be patched up to make it work.
TDK
Super User
November 28, 2025

If you want to connect things without jumper wires, you'll have to make a custom PCB using a program such as KiCad, create that board, and then solder components to it.

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ziminAuthor
Associate
November 28, 2025

I haven’t learn this yet. I need to connect them on donut board by soldering.