There are good reasons for electronics manufacturers to adopt surface mount technology (SMT): It lowers product costs, allows higher component density, and offers improved product performance. Converting legacy thru-hole designs to SMT pays for itself quickly.
Advantages of SMT
In the early days of electronics, boards were assembled using the thru-hole method. This meant drilling holes to accept the long leads on every component. These leads were then soldered to the board.
In the 1980s the industry began switching to surface mount technology. There were three drivers for this:
- Lower cost. Drilling is eliminated, components can be placed and soldered automatically, and it's possible to use both sides of the board.
- Smaller components. Surface mount devices (SMDs) whether active or passive, are more compact than their thru-hole equivalents. This means boards can be smaller and lighter — or more components can be placed on a board.
- Better performance. Eliminating component leads means less inductance and resistance. As result, SMT boards usually perform better and tend to be more reliable.
Despite the clear advantages of SMT, it presents some challenges for designers and manufacturers.
- Not every electronic component is available in a form suitable for SMT.
- Components that may see forces, such as sockets for cables, are sometimes better implemented in thru-hole format as this provides a more durable mount that resists pulling and twisting.
- As land patterns, (the pads where the SMD is soldered to the board), become smaller, components must be placed more accurately.
- Thermal management becomes more of an issue as higher component density increases power consumption and limits airflow over the board.
- Coefficient of Thermal Expansion (CTE) mismatch challenges increase as board temperatures rise.
What Protorun Can Do for You
Converting an older thru-hole printed circuit board assembly to SMT needs electrical engineering expertise coupled with an intimate understanding of surface mount manufacturing processes. Having been in the circuit board business over 30 years, Protorun has the experience necessary to perform the thru-hole to SMT conversion or assembly quickly and accurately: A qualified electrical engineer who makes sure the finished product meets the customer’s needs and expectations oversees every order.
Supporting our SMT manufacturing processes, we also offer extensive inspection and testing. Automated Optical Inspection (AOI) lets us inspect finished boards quickly while our microscope and X-ray services provide additional assurance that they will be defect-free.
Save Money With SMT
SMT circuit boards offer many advantages over older thru-hole technology. Converting thru-hole designs to SMT results in lower manufacturing costs and can easily pay for itself. Protorun has the experience and specialized knowledge needed to perform this conversion quickly and accurately, so ask us if it's time to update your legacy designs.