1. As the main component and key technology of electrical interconnection, Surface Mount Technology (SMT) has become the cornerstone of modern electrical interconnection. Over more than 20 years of evolution, SMT has emerged as the primary technique for PCB circuit component-level interconnection in contemporary electronic products. According to relevant data, SMT application rates in developed countries have surpassed 75%, advancing further into high-density and three-dimensional assembly fields.
2. What is SMT and a placement machine? Surface Mount Technology (SMT) is a board-level electronic assembly process that involves mounting surface mount components (SMD) onto a printed circuit board (PCB). This technology is widely adopted in advanced electronic products, particularly in computers and communication devices.
3. Mounting machines, also known as “placement machines” or “Surface Mount Systems,” are used in production lines after dispensers or screen printers. They precisely place components on PCB pads by moving the placement head. These machines are available in manual and automatic types.
4. What are the advantages of SMT? Emerging alongside the growth of the electronics industry and advancing with developments in electronic technology, information technology, and computer applications, SMT’s rapid adoption can be attributed to its significant advantages. Let’s delve into them.
1) Automation is easily achievable, significantly enhancing production efficiency.
2) Components have high assembly density, and electronic products are characterized by their small size and light weight.
3) High reliability is ensured. Automated production technology guarantees reliable connections at each solder joint. Additionally, surface mount components (SMDs) are either leadless or have very short leads, and are securely attached to the PCB surface, providing high reliability and robustness.
4) Excellent high-frequency characteristics are achieved. SMDs lack pins or have minimal pin segments, which reduces the effects of distribution characteristics. Their firm attachment and soldering to the PCB surface greatly diminish parasitic capacitance and inductance between leads, significantly reducing electromagnetic and radio frequency interference, and thereby improving high-frequency performance.
5) Costs are reduced. SMT increases PCB wiring density, decreases the number of vias, minimizes board area, and reduces the number of layers needed for the same functionality, all of which lower PCB manufacturing costs. Leadless or short-lead SMC/SMDs save on lead material, eliminate trimming and bending processes, and cut equipment and labor costs. Enhanced frequency characteristics also lower radio frequency debugging costs. The reduced size and weight of electronic products further decrease overall machine costs, while improved soldering reliability naturally lowers repair costs.
2. What is the basic process flow of SMT?
The basic SMT process components are: printing (solder paste application) –> inspection (optional AOI automatic or visual inspection) –> placement (first place small components, then larger ones: high-speed placement and IC mounting) –> inspection (optional AOI optical or visual inspection) –> soldering (using hot air reflow soldering) –> inspection (which may include AOI optical inspection, appearance, and functional testing) –> maintenance (tools: soldering station and hot-air desoldering station) –> board splitting (manual or mechanical).
1) To establish an SMT production line, three essential types of equipment are required: a printer/dispensing machine, a placement machine, and a reflow oven/wave soldering machine. Due to the development of surface mount technology and the widespread use of bottom-lead integrated circuit packages like BGA and QFN, the wave soldering process has become increasingly inadequate. Consequently, reflow soldering remains the predominant method.
2) For both mainframe and medium-sized machine manufacturers, Dipeng Classic recommends a typical SMT production line consisting of two placement machines: one high-speed placement machine for chip components and one high-precision placement machine for IC components. This setup ensures that each machine performs its specific role, optimizing the overall production efficiency. However, with the advent of multi-function placement machines from manufacturers like Dipeng, it is now possible to run an SMT production line with just one machine. These multi-function machines can handle all component placements at high speeds, reducing investment costs. This configuration is increasingly favored by small and medium-sized enterprises and research institutions.
The development of placement machines is a focal point in the electronics manufacturing industry. Advances in electronic technology continually demand more from placement equipment, which in turn drives the progress of electronic assembly and technology. Next, I will provide a brief overview of the basic components of a placement machine.
The simplest model of a placement machine is an automatic placement machine, which facilitates high-speed, high-precision automatic component placement. It is the most critical and complex piece of equipment in an SMT production line.
The most basic placement machine consists of a frame, a circuit board clamping mechanism, a feeder, a placement head, a suction nozzle, and X, Y, and Z axes. The Z axis can move in the Z direction and rotate in the θ direction (to adjust the rotation angle of components relative to the pads).
2. What is SMT and a placement machine? Surface Mount Technology (SMT) is a board-level electronic assembly process that involves mounting surface mount components (SMD) onto a printed circuit board (PCB). This technology is widely adopted in advanced electronic products, particularly in computers and communication devices.
3. Mounting machines, also known as “placement machines” or “Surface Mount Systems,” are used in production lines after dispensers or screen printers. They precisely place components on PCB pads by moving the placement head. These machines are available in manual and automatic types.
4. What are the advantages of SMT? Emerging alongside the growth of the electronics industry and advancing with developments in electronic technology, information technology, and computer applications, SMT’s rapid adoption can be attributed to its significant advantages. Let’s delve into them.
1) Automation is easily achievable, significantly enhancing production efficiency.
2) Components have high assembly density, and electronic products are characterized by their small size and light weight.
3) High reliability is ensured. Automated production technology guarantees reliable connections at each solder joint. Additionally, surface mount components (SMDs) are either leadless or have very short leads, and are securely attached to the PCB surface, providing high reliability and robustness.
4) Excellent high-frequency characteristics are achieved. SMDs lack pins or have minimal pin segments, which reduces the effects of distribution characteristics. Their firm attachment and soldering to the PCB surface greatly diminish parasitic capacitance and inductance between leads, significantly reducing electromagnetic and radio frequency interference, and thereby improving high-frequency performance.
5) Costs are reduced. SMT increases PCB wiring density, decreases the number of vias, minimizes board area, and reduces the number of layers needed for the same functionality, all of which lower PCB manufacturing costs. Leadless or short-lead SMC/SMDs save on lead material, eliminate trimming and bending processes, and cut equipment and labor costs. Enhanced frequency characteristics also lower radio frequency debugging costs. The reduced size and weight of electronic products further decrease overall machine costs, while improved soldering reliability naturally lowers repair costs.
2. What is the basic process flow of SMT?
The basic SMT process components are: printing (solder paste application) –> inspection (optional AOI automatic or visual inspection) –> placement (first place small components, then larger ones: high-speed placement and IC mounting) –> inspection (optional AOI optical or visual inspection) –> soldering (using hot air reflow soldering) –> inspection (which may include AOI optical inspection, appearance, and functional testing) –> maintenance (tools: soldering station and hot-air desoldering station) –> board splitting (manual or mechanical).
1) To establish an SMT production line, three essential types of equipment are required: a printer/dispensing machine, a placement machine, and a reflow oven/wave soldering machine. Due to the development of surface mount technology and the widespread use of bottom-lead integrated circuit packages like BGA and QFN, the wave soldering process has become increasingly inadequate. Consequently, reflow soldering remains the predominant method.
2) For both mainframe and medium-sized machine manufacturers, Dipeng Classic recommends a typical SMT production line consisting of two placement machines: one high-speed placement machine for chip components and one high-precision placement machine for IC components. This setup ensures that each machine performs its specific role, optimizing the overall production efficiency. However, with the advent of multi-function placement machines from manufacturers like Dipeng, it is now possible to run an SMT production line with just one machine. These multi-function machines can handle all component placements at high speeds, reducing investment costs. This configuration is increasingly favored by small and medium-sized enterprises and research institutions.
The development of placement machines is a focal point in the electronics manufacturing industry. Advances in electronic technology continually demand more from placement equipment, which in turn drives the progress of electronic assembly and technology. Next, I will provide a brief overview of the basic components of a placement machine.
The simplest model of a placement machine is an automatic placement machine, which facilitates high-speed, high-precision automatic component placement. It is the most critical and complex piece of equipment in an SMT production line.
The most basic placement machine consists of a frame, a circuit board clamping mechanism, a feeder, a placement head, a suction nozzle, and X, Y, and Z axes. The Z axis can move in the Z direction and rotate in the θ direction (to adjust the rotation angle of components relative to the pads).
