In electronics manufacturing, printed circuit boards are separated into three categories: 1, 2, and 3. The categories reflect the level of quality of each circuit board type, from lowest (Class 1 standards) to highest (Class 3 standards). This classification system was developed and is monitored by IPC under the IPC-6011 standard.
Perhaps the major difference between each class is the degree of inspection electronics assemblies must undergo and the quality standards to which they're subjected. Understanding the classes and their requirements can be helpful to OEMs who aren’t sure to which class their product should belong. Factors like customer requirements and cost can weigh heavily into deciding which class to pursue.
Let’s take a look at the IPC class definitions and when you should consider each of them a possibility for your product:
- Class 1 Electronics: General Electronics Products
- Class 2 Electronics: Dedicated Service Electronics Products
- Class 3 Electronics: High-Reliability Electronics Products
IPC Class Definitions
|IPC Class 1||IPC Class 2||IPC Class 3|
|Category||General electronics||Dedicated service electronics||High-reliability electronics|
|Life cycle||Short||Long||Very long|
|Examples||Toys, flashlights, smartphones||Laptops, Microwaves, some mining equipment||Aerospace, military, & medical applications|
Class 1 -- General Electronic Products
The first electronic products class is referred to as the “general electronics” category. This consists of boards with the lowest quality requirements and is mostly found in products with an expected short life cycle.
Think of a superhero toy you’d buy your nephew at Target. It lights up and the echoes the hero’s signature catchphrase with the push of a button. The toy works great for your nephew for weeks after you give it to him, but would you be surprised if the light or one of the buttons stops working after a year or two? Probably not.
This is basically the “get what you pay for” class. These electronics are held to the lowest standard of quality and thus are usually found in cheap, high-volume productions.
Some electronics manufacturers don’t even bother with the class one category. Matric and Dynamic, for example, do not make electronics in class one. All boards manufactured through our facilities are either Class 2 or Class 3, both due to the nature of the markets we serve and our dedication to product quality.
Class 2 -- Dedicated Service Electronic Products
Class 2 electronic devices encompass all electronics where continued performance and an extended life cycle is required -- to a point. Uninterrupted service is desired, but not critical. Along with what's in the chart above, IPC Class 2 examples include:
- Air conditioners
In other words, these are items where an early life cycle failure would have you red-faced and slamming your fist, but wouldn’t put your life at risk.
Something to keep in mind: You’ll want to know which class you want to pursue prior to board design, as products must be specially designed for Class 2 and Class 3 specifications. A board designed for IPC Class 2 specifications can potentially achieve many of the same build requirements for Class 3, but rarely all of them.
Class 3 -- High-Reliability Electronic Products
The third class of circuit boards are subject to strict guidelines due to their importance in the field.
While Class 1 electronics are usually cheap and easily replaceable items and Class 2 electronics are more important and require a longer life cycle, Class 3 electronics are mission-critical items. Whether it’s a pacemaker or a military radar, a product that needs to meet IPC Class 3 requirements must use high-reliability electronic components to ensure uninterrupted service.
These electronics are usually the highest of quality, and many OEM products that could pass as Class 2 opt for the IPC Class 3 standard because the benefits of higher-quality electronics outweigh the cost of additional testing and inspection.
Get the Manufacturer Involved ASAP
Remember, the IPC PCB classes reflect the level of quality of each printed circuit board type, so in some cases it's crucial to make sure your manufacturer is qualified to work with you. Some electronic contract manufacturers only handle Class 1 electronics, so make sure you ask up front. A contract manufacturer that specializes in Class 2 and/or Class 3 electronics may also be able to talk you through factors like customer requirements and cost.
No matter what the case is, make sure to you and you PCB manufacturer are up-to-date on all electronics compliance standards, from RoHs to IPC standards compliance. Check out our free guide to electronics manufacturing standards!
(Editor's note: This article was originally published in August 2018 and was recently updated.)