Surface mount (SMT) and panel mount (THT) are two important technologies in electronic manufacturing, each with its advantages and limitations, suitable for different types of electronic products and applications. Choosing the appropriate technology depends on the requirements of the product, including size, performance, reliability, and cost. In the constantly developing electronics industry, understanding the differences between these two technologies will help manufacturers make wise decisions to meet market demand and maintain competitiveness.
1. Technical Overview
Surface Mount (SMT)
Surface mount is a modern electronic assembly technology that directly installs electronic components onto the surface of printed circuit boards (PCBs) without the need to pass through holes. SMT components have flat pins and are usually fixed to the PCB using welding or bonding technology. SMT technology is suitable for small, lightweight, and high-density electronic products, such as smartphones, tablets, and computer motherboards.
Panel Mount (THT)
Panel mounting is a traditional electronic assembly technology that requires the pins of components to pass through holes on the PCB and then be soldered onto the other side of the PCB. These holes usually need to be drilled during the PCB manufacturing process, and then used for component installation through wave soldering or manual soldering. THT technology is suitable for large, heavy-duty, and high-power electronic products, such as power inverters, amplifiers, and industrial control systems.
2. Process differences
SMT process
High degree of automation: SMT technology typically uses highly automated production lines, including precise robots and visual inspection systems, to ensure efficient and high-quality assembly.
High density: Due to the direct installation of components on the surface of the PCB, SMT allows for higher component density and smaller PCB size, thereby saving space.
Welding technology: Common SMT welding technologies include hot air welding and reflow welding, which can be used to connect component pins and PCB pads.
Small components: SMT is suitable for small and micro components, such as surface mount resistors, capacitors, chips, and microcontrollers.
THT process
Manual process: THT usually requires a lot of manual operations, including manual insertion of component pins and manual welding, resulting in a low level of automation in the production line.
Durability: THT components typically have thicker pins and are suitable for applications that require mechanical stress or vibration, making them more durable in certain situations.
Welding technology: THT usually uses wave soldering or manual soldering technology, which requires the creation of connection holes on the PCB.
Large components: THT is suitable for large and heavy components, such as inductance coils, connectors, and switches.
3. Performance comparison
SMT performance
Electrical performance: SMT components typically have lower inductance and capacitance, which can provide higher electrical performance and frequency response.
Thermal performance: Due to the direct connection of components to the PCB surface, SMT can better disperse heat and help dissipate heat, making it suitable for high-temperature applications.
Signal integrity: SMT can reduce reflection and crosstalk in signal transmission, improve signal integrity, and is suitable for high-speed digital and analog circuits.
THT performance
Mechanical strength: THT component pins are usually more sturdy and suitable for environments subject to mechanical shock or vibration.
High current: THT component pins usually have higher current withstand capacity and are suitable for high-power electronic products.
Repairability: THT components are easier to manually replace and repair because their pins can be easily inserted and soldered.
4. Application field
SMT application field
Consumer electronics: SMT is widely used in smartphones, tablets, televisions, and consumer electronics products.
Communication: 5G devices, communication base stations, and network devices typically use SMT technology.
Computers: Computer motherboards, graphics cards, and memory modules are usually assembled using SMT.
THT application field
Industrial control: Industrial control systems, PLCs, and robot controllers often use THT technology.
Power supply: high-power inverters, power amplifiers, and power modules are usually assembled using THT.
Military and aviation: Military equipment and avionics typically use THT technology because they require higher durability and reliability.
