While obviously factors like safety certifications and margins of error are more important when it comes to safety critical applications, e.g. aerospace, I saw an article that said that one of the remaining areas for through-hole components, is where reliability is important:
- Through-Hole vs. Surface Mount: Through-hole components are best used for high-reliability products that require stronger connections between layers. Whereas SMT components are secured only by solder on the surface of the board, through-hole component leads run through the board, allowing the components to withstand more environmental stress. This is why through-hole technology is commonly used in military and aerospace products that may experience extreme accelerations, collisions, or high temperatures. Through-hole technology is also useful in test and prototyping applications that sometimes require manual adjustments and replacements.
But when googling through-hole vs surface mount reliability, a source painting a more mixed picture popped-up:
- Through-Hole Vs. Surface Mount: Contrasting Benefits and Uses: Disadvantages: Since THT component leads are fed through the board, the PCBs must be pre-drilled, which is both expensive and time-consuming. It also restricts components to one side of the board and limits the available routing area on multilayer boards since the holes must be drilled through all the PCB’s layers. THT’s soldering process often makes the resulting solder points less reliable than SMT solder. Additionally, the THT assembly process is more involved and therefore more expensive than SMT.
Although this source isn't exactly neutral, being a mixed through-hole surface mount vendor. Is there a straight-forward winner when it comes to the reliability of surface mount vs through hole components?