Surface mount technology initially referred to as Planner Mounting, is a technique of mounting electronic components directly onto the surface of printed circuit boards instead of passing them from one side to another and soldering them. In 1960 IBM (mostly) introduced this way of soldering components by using SMT machines. Gradually the industry accepted the revolution of electronic components and started replacing through-hole components with surface-mount components, usually called surface-mount devices (SMDs). A prominent cause of the takeover of SMT over THT is its space-saving feature. In real-time, Surface Mount Devices save a lot of space and provide a better connection between the components and the circuit board.
Nowadays, the industry utilizes both types of components through holes and surface mounts in a single board to maximize performance. Because yet not all electronic components are eligible to adapt surface mount technology. For instance, large transformers and heat sinks.
In this article,
An SMT machine is an automatic assembling machine used to assemble surface mount devices SMDs onto the circuit boards. Usually, an SMT machine is supposed to pick and place surface mount devices in their respective locations.
The automation of SMT assembling has enabled the precise and fast assembly of electronic components. SMT machines aid the manufacturing process of printed circuit boards by minimizing the assembling time and potential errors regarding circuit board assembly.
Surface mount assembling of electronic components does not involve a single automatic device. But, it requires six individual machines to carry out a single task of soldering surface mount components. In this article, we are discussing all six of them.
The first and most essential SMT machine is a pick-and-place machine. The purpose of a pick-and-place machine is to pick the components and place them in their respective locations. To accurately select and drop SMDs, the SMT pick-and-place machine uses the circuit board's layout, pick-and-place file, and Gerber file as references.
The industry divides pick-and-place machines into three groups. These individual machines have various features and are equally significant in different factors.
The three types of pick-and-place-machines are:
Manual pick-and-place machines involve a person who operates the machine to pick and place SMDs. The whole process of picking-and-placing components depends on the operator.
In several ways, manual pick-and-place machines perform better. Such manual pick-and-place machines reduce the risk of placement errors. But, due to the operator's limitation, the manual pick-and-place machines do not ensure component placement accuracy.
However, manual machines are an excellent option for producing a large amount of hand-held work with potential accuracy. The manual pick-and-place machines are also practical for de-soldering and resoldering some particular components on the circuit board. Further manual machines are also ideal for customizing the SMD for high-speed unattended operations.
Semi-automatic pick-and-place machines are a combination of manual and automatic machines. These machines aid the operator and reduce the risk of SMD misplacement. The semi-automatic pick-and-place machines provide a computerized closer view of the circuit board that helps the operator to place the components precisely in their respective locations. Also, the semi-automatic pick-and-place machines provide a set-up of X and Y coordinates that assist the operator in accurately setting the target to drop the surface mount device. This feature of a semi-automatic SMT machine makes it easier to work with massive circuit boards with ultra-thin leads and solder pads.
Automatic pick-and-place machines take over semi-automatic machines with their advanced methods of component placements. Automatic pick-and-place machines are an immense invention as they eliminate human limitations and provide greater accuracy.
Some benefits of an automatic pick-and-place machine include lower labor costs, high accuracy, and enhanced operating speed.
A solder paste screen printer has the function of printing solder paste before the pick-and-placement of components. It mainly consists of two main parts a squeegee blade that directs the poured solder paste in a particular direction and a PCB holder.
But there are two types of solder printing used in the industry screen solder printing and stencil solder printing. The manufacturers usually prefer stencil solder printing due to its high accuracy and controlled process.
The price of an SMT solder paste printer varies depending on the machine's ability to handle the maximum size of the PCB and the speed of the equipment.
Right after the placement of SMDs, the circuit boards need to cure the solder paste to make the SMDs stick to the surface of the PCB. To do so, the circuit boards undergo SMT curing or baking ovens. The SMT curing or baking ovens function as standard household ovens. They provide high-temperature to melt the solder paste and make it a conducting adhesive.
The soldering of surface mount devices involves two steps, adhesive curing, and solder mask baking. Hence, it may require two separate machines for adhesive curing and solder mask baking. Otherwise, a single convection oven can serve both operations.
However, whether to use a single convention oven for adhesive curing, solder paste baking, and reflow soldering depends on the required quantity.
The reflow soldering machine carries out the process of permanently attaching the surface mount devices to the PCB. This machine is responsible for preheating the components and then melting the solder paste to form enduring joints between the SMDs and the circuit board without heat damaging the SMDs.
The soldering process leaves some broza and other sticky materials around the PCB. To clean this mess, the manufacturers use solvent-cleaning equipment. In short, solvent cleaning equipment is responsible for cleaning excess flux and solder from the circuit board left behind during the soldering process.
The repair and inspection equipment is the last machine required to complete the SMT assembly process. The primary function of repair and inspection equipment is to inspect the circuit boards against potential errors. The equipment not only performs inspection but also fixes the detected defects.
Soldering iron and hot air SMD rework stations are the two most common repair and inspection equipment.
Europlacer is another leading surface mount technology SMT machine brand. It provides a complete SMT Line Solution and assures a productivity solution that suits everybody's needs.
So, from the pick-and-place side, the best of Europlacer's production is iineo+. Europlacer claims its iineo+ is a multi-function pick-and-place machine with the highest flexibility level and feeder count in the whole industry. The iineo+ is a modern integrated intelligence-based SMT machine with digital cameras that facilitate a close-up look at the circuit board. A worth-mentioning feature of iineo+ is its ability to produce extra-large circuit boards. It is capable of producing 1610 mm x 600 mm size boards. The iineo++ is one of those machines offering two rotatory heads on X/Y coordinates, each containing 8 or 12 smart nozzles, which help to deliver a maximum placement speed of 30,000 CPH (IPC: 24, 200CPH).
DDM Novastar is one of those leading SMT manufacturers that provides both manual and automatic SMT equipment. It offers a wide range of SMT assembly equipment. Including Manual and Automatic Stencil printers, pick-and-place systems, Benchtops, and Conveyorized and reflow ovens.
DDM Novatars's L-NP00 Benchtop Pick and Place System is an entry-level, low-cost automatic pick-and-place system that delivers in a ready-to-use condition. It is a considerably good system for Prototyping, pilot manufacturing, and low-volume production. The L-NP00 provides placement accuracy of up to 0.004 inches and a placement speed of up to 2,100 CPH.
The DDM Novastar also provides machines with higher capabilities. It was just an example of budget-friendly small-scale equipment.
Yamaha is a specialized company in manufacturing heavy equipment. Its quality can never be in doubt. Along with heavy motor equipment, Yamaha is a leading brand manufacturing high-quality surface mount technology SMT machines. The main focus of Yamaha is the pick-and-place machines that offer exciting placement solutions.
If you want to try something innovative with pick-and-place machines, Yamaha could be the best manufacturer for you to contact.
The Yamaha has an ongoing list of features that proves it a perfect SMT machine manufacturer. Some of them are as follows:
Mycronic is a reputable brand setting the standards of pick-and-place machines on another level. The MY300 of mycronic is its best version of the SMT machine. The operators of this machine state that they are confident about populating more boards with less floor space.
The Mycronic surface mount technology machine has several features, some of which are as follows.
Juki is an experienced, well-known name that produces the best quality SMT machines. The Juki has a lot to offer in the SMT industry, but its brand-new RX-8 has no match. It provides the highest placement rates per square meter and achieves placement of up to 100,000 CPH.
The high-speed compact modular mounter RX-8 supports a board size of 50×50～510mm*¹ *²×450mm and a component height of 3mm. It offers a placement accuracy of ±0.04mm (Cpk ≧1).
Other options from Juki include RX-6R/RX-6B and FX-3RA.
Panasonic has been in the business for more than a century. The company has a firm reputation in the market and offers a complete SMT Line Solution consisting of 5 modules of screen printers, inspection, component placement, inspection, and curing oven. Panasonic focuses on providing Smart Factory Solutions. Their range of machines varies from entry-level to extreme-complex equipment.
Another high-end of Panasonic is that it provides Open Source Software. Its NPM-W2; is one of the best pick-and-place machines with Open Source Software. It offers two types of heads 'Lightweight 16-nozzle head' and '12-nozzle head'. Each category of nozzle head provides an option of High Production Mode On/Off. With high production mode ON on the 16-nozzle head, NPM-W2 provides a maximum placement speed of 38,500 CPH and an SMD placement accuracy of ±40 μm/chip.
The universal instrument is well-known for its electronic automation and assembly equipment. The company offers a wide range of SMT machines for low to high budgets and production needs. From the wide range of universal SMT machines, its FUZION PLATFORM is one of the best SMT machine series that implement the latest head and feeder technologies and software suits. The Fuzion has nine different models with individual features that target specific problems.
ADVANTISV PLATFORM is another series of SMT machines from the universal instrument. It is a pack of mid-range entry-level SMT machines that delivers budget-friendly performance without lacking performance.
Kulicke & Soffa, formerly known as Assemblon, is another leading manufacturer and distributor of Semiconductor, LED, and electronic surface mount technology SMT machines. The company has been providing a reliable service since 1951. Three of the most highlighted SMT assembly products of Kulicke & Soffa include iFlex, iX502/iX302, and Hybrid SiP.
The Kulicke & Soffa's iFlex is a low-energy consuming sustainable, high-yield providing SMT pick-and-place machine. The iFlex has three available modules:
Fuji Corporation built electronic assembly machines and machine tools as their main products. The Fuji corporation provides complete SMT assembly equipment, including
Fuji has a list of brilliant SMT machines, all of which we are discussing in its brand-new NXTR S Model. Fuji's intention with its NXTR series is to smooth the future of smart factories. Hence, NXTR's S model comes with exciting features. Some of these are Real-time sensing placement, Optimized placement actions, and part-handling checks after their arrangement.
Single Action Head Exchange: NXTR S allow operators to change the head without using tools. This feature of the S model enables hassle-free maintenance and troubleshooting.
Minimal Investment: It provides an option to upgrade the module by making additional investments on the scale of single modules to increase production capacity.
Placement: The NXRT S Model can pick and place surface mount devices with all-time high accuracy of ±25 µm, plus it provides placement pressure control.
Placement Checks: The most compelling feature of this machine is its ability to inspect the SMD placement within the placement machine.
Hanwha Precision Machinery built its first chip mounter in 1989, and since then, it has facilitated the SMT assembling industry with the state of the art SMT machines. The Hanwha Precision Machinery offers a wide range of SMT assembling equipment, including surface mount technology mounters, semiconductor equipment, insertion, and assembly automation equipment, and integrated software solutions.
The most highlighted features of the company are its focus on innovation, versatility, and efficiency.
Some of the best SMT machines of
Hanwha Precision Machinery includes:
There are mainly three methods available to position a surface mount device accurately.
No Feedback System uses stepper motors to position SMDs in their respective locations by following the number of steps in each X-Y axis. This system is a low-cost option. The only downside is that it does not accurately indicate whether the component is placed in its accurate position.
The rotary encoders system uses an encoder mounted on the motor shaft of the SMT pick-and-place machine. This encoder sends back the SMD's position to the control system. But the drawback of this system is that it only sends back the position of the machine and not the actual component. Hence, this system of tracking placement positions is also not 100% reliable.
However, this system provides better details than the No Feedback System. Further, this system is low-cost and widely used in entry-level machines and provides a placement accuracy of ±0.005".
Linear Encoder Placement System utilizes linear scales with encoders. The linear scales are mounted on the X-Y axes table, while the encoder is attached to the traveling path that carries the components. It is the only method that provides the actual position of the SMD back to the control system.
However, the quality comes at a price. The linear encoder positioning system is usually higher in cost but provides the best performance and an accuracy of ±0.0005".
The component placement speed of an SMT pick-and-place machine defines its suitability for an organization. Though we have different sizes of organizations, their desired component placement speed varies depending on their production requirements and budget. Hence, the placement speed of the SMT machine is of great importance to study at the initial stages of buying an SMT machine.
Further, the placement rate of an SMT machine elaborates on its productivity and the speed of picking and inspecting the surface mount devices before their positioning on the printed circuit boards.
So, before short-listing any SMT machine, check that against IPC 9850 standards. IPC 9850 is a standard manufacturer used to define the placement speed of their pick-and-place machines.
For an additional note, the placement speed mentioned by the manufacturers is usually 30%-40% extra than the actual value. So, to find an approximate placement speed of a pick-and-place SMT machine decreases the given placement rate by 30% or 40%.
While selecting an SMT pick-and-place machine, you should consider that the component placement speed also depends on the size of the circuit board, type of components, and feeders. If the surface area of the circuit board is large, the machine head has to travel all the way long from one side to another to place components, which will decrease the placement speed and increase the time taken to complete a board.
The SMT pick-and-place machines come up with different numbers of feeder slots and their maximum capacity to store the surface mount devices. The feeder slots and their volume somehow influence the production speed. Thus, when ordering a pick-and-place machine, one should always consider their requirement regarding the component quantity to take out a job successfully. It may be possible for small and dedicated assembly providers to calculate their needs, but for large-scale assembling houses, it is hard to estimate their upcoming requirements. Hence, it is better to select a machine with a larger feeder. Otherwise, order one that suits your needs best.
Bottom Line: To get higher quality production select a machine with a Linear Encoder positioning system. However, if you're short on budget or getting started in the field. Rotary Encoder Systems may get your job done.
Placement Accuracy is another factor one should consider while making an SMT pick-and-place machine purchase. It is highly significant to check placement accuracy as it plays a crucial role in the performance and quality of the circuit board. Machines with higher accuracy always perform better and produce a high-quality yield.
The ideal machine should have an accuracy of 0.0001 and a fine pitch lead of 12 mil.
The part size is another crucial factor to consider. On a random note, a pick-and-place machine should be able to work with these three sizes 0402, 0201, and 01005. If the pick-and-place equipment that you have selected because it meets your other requirements and does not support these sizes, what you could do is buy an additional nozzle or feeder to produce circuit boards with these sizes.
Software is one of the most important factors to consider while buying a pick-and-place SMT machine, as it enables the coordination between the operator and the machine. Any SMT machine of low to mid-volume range should deliver these three primary functions.
Ridong, Jingtuo, Itech, Hopesun Equipment, Autotronik, etc., are some local Chinese brands that provide high-quality SMT machines.
In the US, Universal, Mycronic, and DDM Novastar are some of the most trustworthy and reliable names among consumers.
Panasonic, Juki, Yamaha, Fuji
Assembleon and Mydata
A surface mount machine, especially a pick-and-place machine, plays a significant role in the quality determination of the SMT assembly. Hence, we should be careful while purchasing one for ourselves. There are multiple factors to consider before buying an SMT machine, and the biggest hurdle is finding a good manufacturer. Thus, the NextPCB has provided a list of the top ten manufacturers of SMT pick-and-place machines and complete lineups. NextPCB hopes its effort will help you!