A Surface Mount Technology (SMT) machine is a high-tech generation of equipment that aids PCB makers in solving SMT assembly issues. SMT machines simplify SMT assembly by utilizing fewer components, enhancing performance, and decreasing lead resistance and inductance issues.
This article will discuss the different types and attributes of a good SMT machine.
What do SMT machines do?
SMT machines are for manufacturing surface mount printed circuit boards (SMT PCBs). Examples are soldering equipment, component positioning, and ovens.
SMT machines allow PCB companies to easily fit additional features onto smaller boards instead of using through-hole wire leads to connect components. In addition, SMT equipment can print and fit elements on both sides of a PCB.
For SMT production;
First, an SMT machine applies solder paste to a PCB using a stencil. Then, it places the SMT component on flux-solder paste. Next, the machine runs PCBs through reflow ovens that melt the solder paste and burn-off pieces. Finally, surface tension keeps components intact on PCB solder pads.
(an unpopulated board ready for assembly)
Types of SMT machines
There are up to 6 machines involved in placing electrical components in a PCB. As a result, the input of all these six machines determines the output of an SMT machine.
Below is a list of the various types of SMT machines.
These types of machines come in a variety, which includes;
Manual pick-and-place machines
It is the most widely used and least expensive SMT machine for modular PCB assembly. An SMT operator executes the picking and placement procedure on this machine.
In general, it's an excellent machine for unsupervised high-speed machines.
Semi-automatic pick-and-place machines.
Unlike its manual version, this type has superior computer interface technology and a vision assist. As a result, an SMT operator's job gets easier.
Automated picking and placement.
Pick-and-place machines that are entirely automated are known as automated pick-and-place machines. As a result, the machine includes picking and placement centering methods to boost SMT productivity.
(an automated pick and place machine.)
SMT curing oven
The curing oven is in charge of adhesive curing and solder paste baking. Also, how the process of baking occurs depends on the machines’ volume of production.
Screen printer for solder paste
The screen printing machine works by screen printing solder paste on the PCB. Usually, the screening happens before an SMT Machine Operator begins the assembly process.
Machine for reflow soldering.
The machine operates by allowing the flow of solder from the SMD directly to the Printed Circuit Board.
Solvent cleaning equipment
Normally, after soldering, you'll find a mess of either excess solder or chances of flux. Therefore, this equipment helps to clean up this mess.
This machine operates by detecting and fixing all the detected PCB flaws.
(PCB ready for the assembly process.)
Generally, improvements in feeder technology affect PCB assembly capabilities and production volume. Also, SMT feeders come in a variety of shapes and sizes.
However, this depends on the packaging that various mount components use. For example;
- Tape feeder
A tape feeder has advanced features, thus a high-precision placement machine.
- Tray feeder
A single-layer structure and a multi-layer structure are the two types of tray feeders.
- Stick feeder
A stick feeder and a vibration feeder help to load components into the mounter.
- Tube feeder
The tube feeder ensures that all the components accurately enter the placement head.
(a PCB seen under a Surface mount technology machine.)
How to choose the best SMT machine?
Before choosing an SMT machine, there are a few things to consider.
- Part size
A lot depends on the size of the parts you want a pick-and-place machine to carry. Hence, the size of the machine should match the size of the electronic components.
- Machine accuracy
An SMT machine's accuracy is a vital property when selecting a machine. Besides, 0.0001" is the standard best accuracy of a Surface Mount Technology machine.
- Machine repeatability
Although the SMT machine you choose might be accurate, its repeatability is a critical feature to consider. Importantly, repeatability in a machine helps to generate maximum outputs, especially in a machine that has a computer with programmed software solutions.
- Placement speed
The speed at which an SMT machine picks up, checks, and installs electronic components is an important feature. However, it is important to know that IPC9850 is the standard speed a rapid placement machine should have.
- Prices and cost
Choose a high-speed P&P machine that has features that correspond to the price it holds.
(close up of an SMT machine.)
How to program an SMT machine
There are two steps to follow when programming an SMT machine. The basic procedures involved are offline setup and online debugging.
But before you follow these steps, make sure:
- First, measure the PCB's length, width, and height.
- Have the right mounting information, such as angles, locations, and a tag code.
- Last, the correct details on mark points, the material, and the PCB board assembly.
Offline preparations include:
- First, obtain a BOM list from the customer.
- To retrieve coordinates from an excel or PCB file provided by the customer, you can scan the PCB to get the previously marked locations. Contact your customer for confirmation if the coordinates file is still wrong. Lastly, save it in the format that the pick-and-place machine needs.
After the offline preparation is complete, the online debugging process begins.
- First, load the program into your pick-and-place machine.
- Second, identify the starting point and place a MARK.
- Next, make the necessary adjustments to the reference position number.
- Then, streamline the saving procedure. Also, ensure you double-check the component orientation and data at this stage.
- Finally, run the outcome through FAI for confirmation.
(An SMT operator programming the machine using a computer.)
High-quality SMT machine manufacturers.
Various smart manufacturing companies make SMT machines. But only a few companies make quality machines. For example;
Mycronic is one of the best companies that make SMT assemblies. For instance, the MY300 machine is an interesting SMT that the Mycronic company makes. With the MY300, the operator can fill more boards while using less space on the floor.
Juki Automation Systems.
Juki Automation Systems is a long-time manufacturer and makes quality SMT machines. Normally, Juki focuses on being inclusive. Hence, they make a wide range of SMT machines for companies of all sizes.
Usually, DDM Novastar makes SMT machines used in both automatic and manual SMT systems. Even for low-to-medium SMT applications, their equipment is fairly cheap, easy to use, and reliable.
Undoubtedly, the best companies in SMT manufacturing stand out because of their placement capabilities, superior software, and overall machine effectiveness.
(a PCB board with SMD components.)
SMT machines make work easier, cut costs, and increase production capacity. Before buying an SMT machine, you should know how it works, the different kinds, how to program it, and its qualities.
We hope that our article helped. However, kindly contact us if you're interested in learning more about the SMT machine! Our team is always happy to answer any questions from you.