Joinwin Electronics HK Limited518031About Join WinJoinwin Electronics HK Limited FLAT/RM 29, 22/F, YAN’S TOWER, 25-27 WONG CHUK HANG ROAD,ABERDEEN HONGKONG Shenzhen ZhongYiYingTong Technology Limited Room 1610, Block A, Overseas Decorative Building, Zhenhua Road,Huaqiang North Street, Shenzhen, 518031Join-Win will be your one-stop purchasing assistant. Join together, achieve win-win!Joinwin Electronics HK Limited518031About Join WinJoinwin Electronics HK Limited FLAT/RM 29, 22/F, YAN’S TOWER, 25-27 WONG CHUK HANG ROAD,ABERDEEN HONGKONG Shenzhen ZhongYiYingTong Technology Limited Room 1610, Block A, Overseas Decorative Building, Zhenhua Road,Huaqiang North Street, Shenzhen, 518031Join-Win will be your one-stop purchasing assistant. Join together, achieve win-win!Joinwin Electronics HK LimitedJoinwin Electronics HK LimitedJoinwin Electronics HK LimitedJoinwin Electronics HK LimitedJoinwin Electronics HK LimitedJoinwin Electronics HK LimitedJoinwin Electronics HK LimitedJoinwin Electronics HK LimitedJoinwin Electronics HK LimitedJoinwin Electronics HK LimitedJoinwin Electronics HK LimitedJoinwin Electronics

Home
News
Smd Components Identification,Difference Between SMT And SMD

Smd Components Identification,Difference Between SMT And SMD

September 11 , 2023 0

With the application and development of electronics in modern society, SMT (Surface Mount Technology) is becoming more and more popular because of its small assembly size and high efficiency. However, SMT and SMD are often easily confused and sometimes used interchangeably.
SMT (Surface Mount Technology) is essentially a technical method of arranging components onto a circuit board, while SMD (Surface Mount Devices) are actual assemblies that are mounted on a circuit board according to specific components.

What is SMT

SMT (Surface Mount Technology): A new method of laying out components on a printed circuit board.SMT assembly is a more efficient process where components are soldered directly to the board. By eliminating the need to run leads through the PCB, the process becomes faster, more efficient and more cost-effective. At the same time, SMT assembly is more space efficient, allowing more components to be mounted on smaller boards, which is why many devices are now small in size but have many features.SMT is a complex process where the mounting position of each component is tightly set to ensure that the board achieves optimum functionality. During SMT, an appropriate amount of solder paste is applied evenly to the board before the machine mounts each component. However, mounting components directly on the surface is more efficient than routing them through the board, allowing the entire board to run faster and with less surface area.In addition, surface mount technology offers the possibility of automation, whereby machines can be programmed to mount selected components directly onto the PCB in a short time. This means faster production processes, higher quality and less risk.

Surface mount technology process SMT process, the use of surface mounting machine (SME), the surface mounted components (SMC) and printed circuit boards (PCB) assembly process, there are three main processes:

Solder Paste Printing Process
The surface mounting machine used: Automatic Solder Paste Printer.
Pickup and Punching Process
Surface mounting machine used: Pick & Placement Machine
Reflow process
Surface Mounting Machine: Reflow Oven
Below is a simple diagram of the overall surface mounting technology. A 0603 resistor is used as an example to illustrate the process. First, the PCB must be cleaned and solder paste is printed onto the pad using an automatic solder paste printer. At this time, the paste is in the form of a paste covering the pad. Next, a pick-and-place machine is used to place the 0603 resistor in the correct position. At this time, the solder paste is still in paste form, and the resistor will sink into the paste by its own weight and be fixed in the desired position. The circuit board will be heated by the reflow oven, the solder paste will be hardened by the heat, the hardened solder paste will combine the circuit board and the resistor tightly, at this time, all the processes of surface mounting technology are completed.

Advantages Of SMT Assembly:

Assembling electronic products with SMT has the advantages of small size, good performance, complete functions and low cost. Widely used in aviation, communications, medical electronics, automotive and home appliances. High assembly density, small size and light weight of electronic printed circuit boards. The volume and weight of the chip assembly is only about 1/10 of the traditional plug-in assembly.After SMT is generally used, the volume of electronic PCBA is reduced by 40% to 60%, and the weight is reduced by 60% to 80%. High reliability, high shock resistance, low solder joint defect rate. Good high-frequency characteristics, reducing electromagnetic and radio frequency interference. Easy to automate and increase productivity. Reduce costs by 30% to 50%. Save material, energy, equipment, labor, time, etc.

SMD / SMA / SMT / SMC / SMP / SME

What Is SMD

SMD (Surface Mount Device): The actual component mounted on a printed circuit board. Today, newer SMDs use pins that can be soldered directly to the PCB instead of using leads to route through the board. The advantages of using pins versus leads are many, for example, smaller components can be used to fulfill the same function, which means that more components can be mounted on a smaller board with added functionality. At the same time, the mounting process is faster and more cost-effective as there is no need to drill holes in the board. In contrast to the manual soldering of SMDs in the past, today it is possible to mount SMDs (such as resistors, ICs and other components) automatically on the surface of the PCB, and with the correct layout process, SMDs can be operated at a highly efficient level for a longer period of time. In summary, the main difference between the two is that one refers to the mounting process (SMT) and the other to the actual component (SMD). However, in many cases, the two overlap: for example, the correct selection and arrangement of SMDs is the main SMT process, while SMT assembly is the workflow or strategy used to use SMDs more efficiently.

SMD Common Package Size

Advantages of SMD package size SMD:

The actual copper foil size of SMD pads is larger than that of NSMD, and the pads are covered and pressed with anti-soldering oil, so the bonding strength between the pads and the FR4 is relatively better, and the pads are less likely to be dislodged due to repetitive heating when repairing or reworking the pads.　　

Disadvantages of SMD:　

SMD pads have relatively poor solder strength. This is because of its relative tin eating area becomes smaller, and SMD pads around the pressure of the anti-soldering oil, these anti-soldering oil in the flow through the soldering high temperature thermal expansion and contraction, but also affects the junction of the solder and green paint tin eating effect.　　When affected by the stress, it is easy to break from the surface of the pad.　　PCB Layout will be more difficult to route, because the spacing between the pads becomes smaller.

Conclusion

Finally, using the right technology can dramatically improve prototypes. For example, automated SMT machines are capable of mounting thousands of SMDs onto a board in a short period of time. In addition, the choice of SMDs will determine the effectiveness of the overall SMT, which determines the physical capacity of the electronic boards (zones), and the SMT, which installs these components onto the boards in a timely manner.