Contract Electronics Manufacturing and PCB Assembly Blog

Why You Should Look To SMT For Your Next Circuit Build

Posted by Matthew Turpin on Tue, Sep 30, 2014 @ 07:00 AM

smtFor most of the history of manufactured electronics, "through hole" printed circuit boards have been the standard.  The idea has been effectively unchanged since the 50s, although there've been improvements in size and manufacturing quality.  A through-hole circuit board needs holes drilled through it for connections and circuitry to pass through.

More recently, a new manufacturing style has emerged:   Surface-Mount Technology. SMT circuit boards don't use holes and instead use a combination glue and solder to hold components in place.

While not right for every electronics build, SMT has many distinct advantages over the older style of circuit design.  Let's look at the major differences, and why SMT might be the right tech for your next product!

The Benefits Of Surface-Mount Circuitry

1 - Reduced Size

Arguably the single biggest reason to use SMT is also the smallest:  It's much more space-efficient.  Not having to leave room for holes and pass-throughs means that your designs can be more compact.  In a world where most electronics manufacturers are looking for the smallest and "cutest" designs, SMT can make a major difference in your final form-factor.

If you've been designing your circuits for through-hole production, you might be surprised at how much space SMT can save, without  compromising quality.  

2 - SMT Is Easily-Automated

While automatic plants for through-hole circuitry exist, they're usually more expensive and slower to run.  The need to thread wires and attach components to anchor points makes it more likely human hands will be needed to complete assembly.

On the other hand, SMT circuits can simply be stamped, part by part, directly onto the board.  Again, this is thanks to the combined glue/solder.  Without the need for so many wires, the boards can be stamped out much more quickly.  That means less cost to you.

3 - Two-Sided Stamping

A through-hole circuit board is largely limited to only having components on one side of the board, because the other side is reserved for the wires and other circuitry.  SMTs, on the other hand, are agnostic about component placement.  

Both sides can be utilized equally which, again, shrinks the size of the final component, and lowers your costs on manufacturing.  And on the topic, did we mention that SMT components are usually cheaper than those used in through-hole boards?

Why You Might NOT Want SMTsurface mount

As we said above, SMT isn't right for every situation.  There are two major situations where through-hole is still the better option.

1 - High Voltage Requirements

That clever glue/solder is, at the end of the day, not as good for carrying high voltage loads as regular wiring.  While SMT is fine for most consumer goods, if you're producing a product that requires a large battery or high voltage to function, you'll likely want a through-hole build.  You'll get steadier voltage and more reliable performance.

2 - High Physical Durability Requirements

Most SMT boards are not as durable as though-hole, especially if the electronics themselves are expected to be treated less-than-politely by the end users.  SMT is especially poor for open connectors (like USB ports) because it can't handle mechanical stress.

Likewise, products for children should be through-hole to prevent breakage.

SMT should be used when the circuitry will be self-contained, locked away from the user, and unlikely to see much direct interaction.  Use through-hole otherwise.

Which Production Technique Is Right For You?

Zentech is among America's top electronics assembly firms, proudly staying in the USA despite the urge to outsource.  We maintain top-flight manufacturing centers that are ready for any job, whether it's SMT or through-hole.

For a consultation on your production options, just contact us for an evaluation.  We'll look over your designs, suggest improvements, and work out the perfect solution for mass-manufacturing.

Contact Zentech today for more information!

Electronic Interconnect Cabling Whitepaper from Zentech

Topics: assembly manufacturing, consumer electronics, smt production