What is High Volume PCB Assembly and Why Is It Important?

High-volume PCB assembly using automated equipment

Do you need your circuit boards assembled in large batches? High-volume PCB assembly offers many benefits, making it a better choice when producing PCBAs in bulk. Below, we discuss how it works and how to use it to attain your project goals. We will also show you what to consider when seeking PCBA services.

What is high-volume PCB assembly?

High-volume assembly is when a manufacturer assembles your printed circuit boards in large batches totaling over 1,000 in a single production cycle. It contrasts with low-volume assembly, where numbers can be as low as 100 or less.

High-volume assembly is popular when manufacturing consumer electronics PCBs. Other industries where this service is valuable include automotive, aviation, power electronics, lighting, communication, and defense or military.

Automated mass production of PCB assemblies
Automated mass production of PCB assemblies

How are High Volume Circuit Boards Produced?

With its higher production requirements, PCB assembly can only partially rely on traditional manufacturing methods. Instead, automation plays a more significant part, from the solder paste application and component placement steps to soldering and testing. Here is what happens.

1.Solder Paste Printing

The assembly process begins with applying solder paste to the bare boards. Two application methods are available: the traditional stencil and modern jet printing.

Stencil printing offers precision and faster application speed. However, the stencil takes time to make, which can reduce the turnaround time. As such, many manufacturers prefer jet printing for high-volume PCB manufacturing.

Jet printing offers more flexibility, allowing manufacturers to assemble different board designs without having to create a different stencil every time. It also doesn’t take time to set up: you only need a computer program to control the applicator movement.

2.Pick and Place Machine

After the solder paste application, the PCBs are now ready to be assembled with components. Again, automation hastens the process and reduces human errors, allowing manufacturers to produce large numbers of PCBAs quickly.

A feeder system supplies the required components to the pick-and-place machine. A robotic head then picks up the parts and places them on the circuit board. A computer program controls its motions, ensuring greater accuracy.

Placement speeds vary, with some machines averaging thousands of components per minute. These machines play a significant role in ensuring the success of the large-volume assembly processes.

3.THT vs. SMT Component Placement

PCB assembly can use THT through-hole or SMT surface mount technology to place components. SMT is quicker and more preferred when assembling boards in large volumes or batches. It’s also more automation-friendly.

4.Reflow Soldering

With the components in place, the circuit boards now go to the soldering stage. Reflow soldering is preferred when assembling SMT components, although you can use it for thru-hole parts.

It involves gradually heating the boards in a reflow oven to melt the solder paste. The boards go to a cooling station where the solder solidifies to form strong bonds that firmly hold the components and establish secure electrical connections.

Reflow soldering offers speed, a significant part of mass production, when assembling circuit boards in large batches. It also ensures soldering uniformity for guaranteed PCBA quality.

5.Automated PCBA Inspection and Testing

The assembled boards are now ready for inspection and testing. Manual inspection is slow and prone to errors. For higher-volume circuit boards, automated systems are a better option.

AOI (automated optical inspection) equipment uses various light sources to scan the board surface and high-resolution cameras to capture images. Computer software analyzes these images to identify assembly defects.

Other PCBA inspection and testing methods include 2D or 3D X-ray imaging, the flying probe test, in-circuit testing, and the functional test, where the manufacturer checks the board for its ability to perform its end-use functions reliably.

The benefits of large-volume PCB assembly include product uniformity
The benefits of large-volume PCB assembly include product uniformity
Resource: https://youtu.be/KkgSrBuell0?si=kDnLckOdt6x2ZCKH

What are the Benefits of High Volume PCB Assembly?

High-volume PCB manufacturing offers many benefits, making it a popular way to produce PCBAs. The advantages include reduced cost, increased automation, shorter time to market, and board uniformity.

Cost Reduction

Mass-produced circuit boards offer the benefit of economies of scale, which drastically reduces costs. You get to produce your boards cheaply, giving you an upper hand in your target market. On the other hand, low-volume PCB assembly increases the per-piece costs, reducing your project competitiveness.

Increased Automation

There’s more reliance on automation and reduced use of manual procedures, from the solder paste application to the inspection and testing stage. Automation ensures uniformity, increases manufacturing speeds, and lowers production costs. It also reduces human errors, which enhances product quality.

Shorter Time to Market

You get to produce your boards in large numbers and quickly, which means a shorter time to get your product to the market. On a larger scale, it gives you an edge over your competitors and allows you to meet your assembly projects’ deadlines.

Consistency and Uniformity

You get more uniform circuit boards, which guarantees quality. If your boards were adequately designed and prototyped for testing, it means assured product quality and reliability. It reduces the possibility of faulty circuit boards and minimizes the chances of losses.

Using automation in PCB assembly manufacturing
Using automation in PCB assembly manufacturing
Resource: https://www.youtube.com/watch?SRu02F6AOmg


PCBA production is usually low, mid, or high volume. High-volume PCB assembly offers many benefits, making it a better choice when producing PCB assemblies for consumer devices and other applications. In this guide, we discussed the benefits of assembling circuit boards in large batches and how to choose the assembler for your project. We hope the information helps you get started with your project.


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