PCB through hole technology involves the use of drilled holes on a printed circuit board (PCB) to create an electrical connection between different layers or components. The PCB through hole process is common in electronic manufacturing as it provides stronger and more reliable connections compared to surface-mount technology.
During the PCB through hole assembly, the manufacturer drills small holes into the PCB at specific locations where interconnections are required. These holes are then plated with copper to form a conductive pathway through the hole that connects the two sides of the board.
Components such as PCB resistors, PCB capacitors, and PCB diode can be inserted into the through-holes either manually or using automated inserters, ensuring secure positioning and electrical contact. Soldering them to the PCB’s pads provides additional mechanical strength and better conductivity.
What is PCB through hole
PCB through hole refers to a type of circuit board connection where components are inserted into holes drilled in the board and then soldered onto the copper pads on the other side. These connections are called through-hole connections because the component pins go all the way through the board instead of being surface-mounted like they would be with SMD (surface-mount device) technology. Through hole connections are often used for larger or higher-power components, as well as for components that need more physical support or durability than can be achieved with SMD connections.
What are the advantages of a through hole in PCB
1. Strong and Durable Connections: Through-hole components are securely mounted onto the PCB, resulting in a durable connection that can withstand vibrations and mechanical stress.
2. Easy to Solder: Through-hole components are easier to solder than surface-mounted components.
3. Accessibility: Through-hole components are often larger than SMDs and accessible from both sides of the PCB.
4. Reparability: In case of any issues with the component, the through-hole design makes it easier to replace or repair the component without requiring an entirely new PCB.
5. Circuit Reliability: Through-holes help in providing a high level of circuit reliability by minimizing the chances of short circuits or disconnected components.
What are the standards for PTH hole size
The standards for PTH (plated through-hole) sizes vary depending on the application and the type of technology being used. However, some commonly accepted standard sizes are:
– Minimum finished hole size: 0.2 mm (~8 mils)
– Maximum finished hole size: 5.0 mm (~200 mils)
– Standard increments in finished hole diameter: 0.1 mm (~4 mils)
– Tolerance for finished hole size: ±0.05 mm (~2 mils)
– Annular ring size: at least 0.05 mm (~2 mils) larger than drill diameter
– Aspect ratio: typically up to 6:1 or 8:1, but can be higher with advanced technologies.
It is important to note that these standards may differ based on the specific requirements of the PCB design and the manufacturer’s capabilities. Therefore, it is recommended to consult with the manufacturer to ensure compliance with their specifications.
What are the precautions for PCB through hole design
1. Keep the component lead diameter in mind to ensure that the hole size is appropriate.
2. Avoid overcrowding components or routing traces close to through holes to prevent short circuits.
3. Make sure that plated holes are designed with the correct diameter and clearance to prevent overetching during the PCB fabrication process.
4. Avoid placing large components that generate heat, such as power supply or amplifiers, near through holes.
5. Protect the board from excess heat to prevent the through-hole plating from melting or cracking.
What is the PCB through hole technology
PCB through hole technology is a method of mounting electronic components on a printed circuit board (PCB) by inserting component leads into holes drilled through the board and soldering them in place on the opposite side. This method provides better stability, reliability and mechanical strength than surface mount technology especially for larger-sized components like connectors, transformers or power devices that require high currents. It was widely used in the past but now it has been largely replaced by surface mount techniques due to their smaller size and cost-effectiveness.
What are the differences between through-hole mounting and surface mounting
Through-hole mounting and surface mount technology (SMT) are two different methods of mounting components on a printed circuit board (PCB). The main differences between the two are:
Components:
Through-hole mounting components have leads that pass through holes in the PCB and are soldered to the opposite side of the board. These components are generally larger and can handle higher levels of voltage and current. Surface-mounted components, on the other hand, are much smaller and do not have leads. They are mounted directly onto the surface of the PCB.
Technology:
Through-hole mounting technology is an older method of mounting components and is more suitable for traditional circuits with a lower level of complexity. Surface-mounting technology allows for much smaller and more complex circuits to be designed due to the smaller size of the components and their ability to be mounted on both sides of the PCB.
Process:
Through-hole mounting requires the drilling of holes (PCB drilling) on the PCB and manually mounting and soldering the components to the board. Surface-mounting uses special machines to place the components on the PCB, and then soldering them with automated placement and soldering machines. This automated process makes surface mounting much faster and more efficient than through-hole mounting.
How to soldering PCB through hole well
1. Soldering iron with adjustable temperature
2. Soldering wire (with flux core)
3. Soldering Stand
4. Desoldering pump or solder wick
5. Soldering flux
6. PCB board
7. Components with through holes
Here are the steps to solder PCB through holes well:
1. Clean the PCB board and the components to remove dirt, dust, or any oxide residue.
2. Insert the components into their corresponding holes on the board and align them properly.
3. Secure the board and the components in place using a helping hand tool or a holder.
4. Ensure that the soldering iron is at the right temperature. This will be dependent on the type of wire that you’re using, as well as the size of the component that you’re soldering.
5. Apply a small amount of soldering flux on the through-hole and the pad on the PCB. This will help the solder to flow and adhere to the surface.
6. Hold the soldering iron tip on the pad for a few seconds until it heats up.
7. Check the solder joint visually to ensure that there are no cold solder joints or bridges between pins.
8. Repeat the process for all the through holes.
If you make mistakes during the soldering process, you can use a desoldering pump or solder wick to remove the excess solder. Be careful not to overheat the board or the components, as this can damage them.
How do you plate PCB through the hole well
1. Properly clean and degrease the PCB surface before plating to ensure good adhesion of the plating material.
2. Create good-quality holes to ensure uniform plating and avoid any voids or air bubbles.
3. Use an electroplating solution specifically designed for PCB plating through holes. This will ensure good adhesion of the plating material to the PCB surface.
4. Use a plating bath with high agitation to ensure uniform plating of the through holes.
High-speed PCB design-through hole or via-in-pad
The design of high-speed PCBs is a crucial part of electronic product development. One of the essential aspects of high-speed PCB designs is routing, which can be done through holes or via-in-pads.
Through-hole technology (THT) involves drilling a hole in the printed circuit board (PCB) and inserting the component leads through the hole before soldering it to the other side of the board. THT is an older method and is not suitable for high-density circuit boards.
Via-in-pad technology, on the other hand, allows designers to use smaller pads while providing space savings, thermal management, and signal integrity benefits. In this technique, the via itself is placed inside the pad, making full use of the available board area.
As such, if you are designing a high-speed PCB, consider using via-in-pad technology instead of traditional through-holes to offer superior performance.
Conclusion
In conclusion, through-hole technology still plays an essential role in the production of printed circuit boards. Although surface mount technology has gained popularity due to its advanced capabilities, through-hole technology is still essential for connectors, heavy components, and mechanical support.
Despite the challenges involved in its implementation, through-hole technology remains a crucial aspect of PCB design, construction, and assembly, especially in complex and mission-critical applications where reliability and durability are imperative. Overall, the continued existence and evolution of through-hole technology demonstrate its enduring value in the electronics industry.
PCB through hole refers to a type of circuit board connection where components are inserted into holes drilled in the board and then soldered onto the copper pads on the other side.
The standards for PTH (plated through-hole) sizes vary depending on the application and the type of technology being used. We list some commonly accepted standard sizes in our article.
1. Soldering iron with adjustable temperature
2. Soldering wire (with flux core)
3. Soldering Stand
4. Desoldering pump or solder wick
5. Soldering flux
6. PCB board
7. Components with through holes
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Author
Kate
My name is Kate and I am an electronic engineer with 5 years of experience in IBE Electronics, especially in PCB-PCB design and assembly, electronic components and other related fields. Major in electrical engineering and I have been working in the electronics industry since I graduated in 2018. My greatest passion is to share all the PCB and PCBA knowledge I know with people I meet through articles or communications, whether you are new to the industry or seasoned experts.