Quick Turn PCB Assembly: What It Is and Its Benefits

Quick-turn PCB assemblies are critical for electronic projects because they hasten production.

They save time because you won’t have to change the board after manufacturing.

Also, they cut costs by avoiding rework via prototype manufacturing before product fabrication.

In a nutshell, this circuit board production process involves prototyping, pre-production, and production, and here’s all you need to know about it.

What Is a Quick Turn PCB Assembly?

Quick-turn is a short form for quick turnaround time. So quick turn PCB assemblies refer to printed circuit boards that undergo fast manufacturing and assembly.

This production process can last 24-72 hours (1-3 days).

The process is suitable for all PCB designs and does not compromise quality.

Although more expensive than regular PCB production, quick-turn PCBs will hasten your production runs. So you’ll be able to deliver your products to market quickly.

Quick Turn PCB Assembly Benefits

The primary advantage of quick-turn PCBs is you can get your products produced quickly and efficiently.

This benefit introduces several secondary advantages, including the following.

Assisting in determining the DFM (Design for Manufacturability), which further minimizes the time to market and project cost
Enabling faster idea, component, and prototype testing
Producing a few prototypes quicker for design enhancement and validation
The few prototypes help determine the product efficacy before embarking on large-scale production.

Factors Affecting The Turnaround Time for PCB Assemblies

Although quick-turn PCBs take a short time to assemble, these parameters affect the production time.

Design Complexities and Test Procedures

Complex designs lengthen the turnaround time. So always adhere to Design for Manufacturing guidelines by verifying component availability before going into manufacturing.

This process will ensure you design boards with components readily available to the manufacturer/assembler for quick production.

Similarly, adhere to Design for Testing guidelines by providing the testing requirements and protocols before production begins.

Once everything is clear, manufacturing and assembly will take a short time, reducing the turnaround time.

Lamination Cycles

Each lamination cycle increases a board’s lead time because it is equivalent to adding another layer to the PCB. Usually, it takes 4-5 days to handle every lamination cycle.

But this duration varies depending on the material used and the number of layers in the PCB stack.

It is vital to note that HDI boards with multiple via structure types require sequential lamination cycles.

So the more types of via structures, the more the lamination cycles, which increase the lead time.

Via-in-Pads

Molten solder can wick through the plated vias, adding at least one day to the cycle time to rectify the issue.

But these vias are necessary to save space or evacuate heat, such as in ball grid array soldering.

So with more via-in-pads, the turnaround time is likely to be longer.

A circuit board with gold-coated BGA pads

Surface Finish

There are different surface finishing techniques, and each takes some time to apply.

For instance, HASL (Hot Air Solder Leveling) takes at most 20 minutes, but ENIG can take up to two hours.

So your board’s turnaround time can increase if you have to include two or more finishes.

For instance, you might need a hard gold layer electroplated on gold fingers and ENIG for other areas. You cannot apply the two concurrently. It must be sequential.

Gold-coated contact pads on a PCB

Fabrication Drawing Specifications

Fabrication drawings contain vital board manufacturing information, including the following.

IPC class
Via drill chart
Layer stack up
Materials
Mechanical dimensions
Plating thickness

While preparing this document, consider the manufacturer’s abilities to actualize your design.

You will increase the lead time if you create one with requirements that exceed the manufacturer’s capabilities.

For instance, consider things like material availability and minimum trace width.

Also, ensure the document correctly specifies the trace width, target impedance, etc., to avoid information mismatch delays.

Assembly Drawings

Before sending assembly drawings, ensure you have the following.

A complete BOM that includes component descriptions and part numbers
Legible silkscreen markings
Adhered to all DFA guidelines
There are no component footprint mismatches

An electronic PCB concept

Factors To Consider When Picking Your Quick Turn PCB Assembler

Check and compare these five factors.

Experience

Fabricating and assembling PCBs is already a complex process. So building them faster is more complicated.

Therefore, consider an assembler’s experience in fabricating and assembling quality products.

Quick Turn PCB Assembly: Delivery Time (Speed)

Always confirm an assembler’s delivery time before agreeing to the contract and making payment.

The production time should match your production schedule to eliminate delays.

Quick Turn PCB Assembly: Product Quality

While hastening the product manufacturing and assembly, ensure the manufacturer does not compromise product quality. This factor can be challenging to determine.

But you can ask for certifications and other documents to show proof of high-quality PCB production.

Quick Turn PCB Assembly: Equipment

Advanced manufacturing and assembly equipment enables quality production.

So if you can’t visit the factory to see what the assembler has, ask for an equipment list.

PCB assembly equipment

Cost

Lastly, the manufacturing and assembly costs must fit within your budget.

So compare the service providers based on the price quote after checking all the above factors.

Factors Determining the Cost of Quick Turn PCB Assembly Services

Since cost is a critical factor, designers must consider these factors.

Quantity of boards
Machine and labor costs

Delivery time
Assembly technologies

A PCB with a mixed assembly

Wrap Up

Although quick-turn PCBs cut costs by avoiding rework, they are generally more expensive to build than regular boards.

However, they have several benefits that make their high production costs worth it.

And you can consider the factors above to reduce the costs further.

But more importantly, pick the correct assembler using the considerations above.