It might be necessary to slow down the surface mount machines to ensure the desired placement accuracy (which will mean a longer build time and additional cost). However, achieving that standard may also come at a premium. Typically, the Class 3 standard will be aimed at more critical printed circuit board assemblies. This will include laminate selection, plating thickness, material qualifications, manufacturing processes and inspection. The highest standard of the IPC classes is Class 3, which means an electronic assembly must be built in accordance with all of the IPC criteria.
Surface mount components that have been placed slightly ‘off pad’, for example, are usually still fine electrically and mechanically, even though aesthetically they may look wrong. IPC-A-610 Class 2Ĭlass 2 of the IPC standards is typically the most requested for non-critical electronic assemblies where longer-term reliability is desirable, but perhaps not essential.Ĭlass 2 does still allow for a certain degree of imperfection.
The product is also likely to be manufactured to very tight margins (read "as cheaply as possible") so as long as the item still functions as expected (and its operational life sits within an acceptable time-frame) then that's probably going to be sufficient. When we think of the functionality of the electronics assembly within a simple toy, for example, the PCBA is likely to be hidden well away inside the body of the item so the quality of the solder joints or component positions may not be such a high priority. As an Original Equipment Manufacturer (OEM) it’s important that you're clear on the basic principles that separate those classes so you have a clear and realistic expectation of what the end results are going to be.Ĭlass 1 of the IPC standards is the lowest of the Classes, and so the most 'lenient' when it comes to making allowances for potential defects.
The standard comprises of three classes - 1, 2 and 3. Within that, there’s also a fair amount of scope for things to be 'good', or 'bad', or somewhere in between.įor many Electronics Manufacturing Services (EMS) providers the IPC-A-610 Acceptability of Electronic Assemblies is the agreed standard that we use to define what's acceptable, and what's not, in the world of PCBA production. There’s the printed circuit board itself with all its material and finishes, its various components, and the solder that holds everything together. If the assembly works as intended then surely that indicates a certain level of acceptability, right?īut what about the product's longer-term reliability? And what if you'd also like it to 'look good' too?Ī Printed Circuit Board Assembly ( PCBA) is a surprisingly complex thing. When you think about what makes a ‘good’ electronics assembly, what are the most common expectations that come to mind?