As a new generation of electronic assembly technology, SMT can develop so fast, mainly because SMT has the following advantages compared with traditional THT.
(1) High component assembly density, light weight and small size of electronic products. The surface-mount components are much smaller than traditional through-hole components. The surface-mount components only occupy 1/3-12 of the printed circuit board, and the surface-mount components are only through-hole. 1/10 of the components, the volume of electronic products can be reduced by 40% to 60%, and the weight can be reduced by more than 80%.
(2) Strong seismic resistance and high reliability. Due to the small size and light weight of the surface-assembled components, the anti-vibration capability is strong. The soldering reliability of surface-mount components is higher than that of through-hole components. Therefore, the average time-to-failure time of surface-assembled electronic products is generally 200,000 hours or more, so reliability is high.
(3) Good high frequency characteristics. Surface-mount components have no leads or short pins, which reduces the influence of pin distribution characteristics, and has a strong and reliable soldering surface on the printed circuit board, greatly reducing parasitic capacitance and parasitic inductance on the circuit. The effect is to greatly reduce electromagnetic interference and radio frequency interference, which reduces the noise of the components and improves the high-frequency characteristics of the components. (4) High degree of automation and high production efficiency. Compared with THT, SMT is more suitable for automated production. According to the different components, THT requires different instrumentation equipment, such as jumper, radial inserter, axial inserter, etc. The equipment production preparation preparation time is longer, and because the aperture of the through hole is small, the insertion The accuracy of the installation is also poor, the workload of the repair is also large, and the machine must be shut down when refueling, which increases the working time. SMT can complete the placement task on a universal machine, and has the function of non-stop refueling, saving a lot of time. At the same time, because the related equipment of SMT has visual function, the placement accuracy is high, and the correction amount is low. This makes automation and production more efficient.
(5) Cost reduction. SMT can perform double-sided mounting of printed circuit boards, making full use of the surface space of printed circuit boards, and using SMT, the number of drilled holes in printed circuit boards is reduced, the aperture is tapered, and the area of printed circuit boards is made. Significantly reduced the manufacturing cost of printed circuit boards. Part of surface mount components also cost less than through-hole components. At the same time, with SMT, the corresponding repair work is reduced, reducing labor costs. In addition, surface-mount components are small and lightweight, reducing packaging and shipping costs. Under normal circumstances, after the adoption of SMT in electronic products, the total cost can be reduced by more than 30%.