Reputable electronics manufacturers insist on PCB testing
The Printed Circuit Board (PCB) has been around for almost a century and it forms the foundation upon which modern electronics are built. To compete in today’s market, an in-depth testing mechanism must be part of the production process to ensure high-level PCB Quality Contol (QC). Unfortunately, some manufacturers cut this crucial step short in order to meet low-end estimates and expedited turnaround times. In the end, making it to market fast comes at an expensive cost: faulty products are returned for refund and accompanied by negative reviews. It’s better to take the time to test your product so it hits the shelves ready to deliver a return on investment over the long run. Testing saves money.
How does an electronics manufacturer improve PCBs with testing services?
Let’s take a look.
An In-Circuit Test
The In-Circuit test (ICT) is one of the most robust tests performed on mature products where few revisions are expected or needed. It involves probing individual components of the PCB to test that they work.
You can enter the components via pre-designed access points. This makes it easy for the ICT probes to connect with the circuit. In short, it’s a capacitance test of component values, short circuits, the operation of ICs, and short circuits.
There are two kinds of ICT:
- The standard test: This is more cost-effective with a faster turnaround
- The advanced test program: This is better suited to more complex boards at the ICT stage
Sometimes, the ICT is combined with the Functional Test (you’ll read more about the Functional Test below) into a single-stage test. This is designed to obtain the highest possible fault detection coverage.
This type of test will save time, money, and reduce the potential for errors further down the line.
Flying Probe Test
A more cost-effective alternative to the ICT test, the flying probe test is electro-mechanical and typically checks for capacitance, inductance, diode issues, opens, resistance, and shorts on a PCB assembly quickly and accurately. Needles attached to an x-y grid probe various components. This includes SOICs (small outline integrated circuits), PGAs (pin grid array), SSOPs (small outline integrated circuits), and QFPs (quad flat package).
The Flying Probe test verifies larger boards, PCB sample boards, PCB prototypes, and PCB production ramp-up.
X-Ray Inspection
X-Ray inspection is also referred to as an AXI test. It’s a high-resolution 2D or 3D scan that tests large boards, BGAs (ball-grid array), micro BGAs, and chip-scale packages. The test allows trained and experienced technicians to look at barrels, internal traces, and connections. An X-Ray inspects PCB parts that are difficult to see otherwise. The AXI test can detect faults such as doming, voids, insufficient reflow, potato chipping, opens, and shorts.
Automated Optical Inspection
Widely used by electronics manufacturers, the AOI test uses a high-speed 2D or 3D computer camera that scans for wrong parts, missing components, height variations, solder integrity, lead defects reverses, and positional divergence on the PCB board. Although automated, the scans are checked by a technician if there’s any variance between the scan pictures. A detailed PCB diagram is also used to inspect them. Some manufacturers will conduct an AOI in conjunction with other tests such as the Flying Probe or IC test. This type of test is helpful if you use it after manufacturing soldered PCBs because it can quickly detect any irregularities or errors. When these come to light, you can promptly rectify them before further manufacturing continues.
Burn-In Test
Used to dig out irregularities and failures early on in the PCB manufacturing process, the burn-in test is intense. It’s also used to establish load capacity and is often used to test PCBs intended for military and medical equipment.
As the test is so intense, the burn-in can destroy other parts. It pushes power through a PCB at whatever the maximum capacity is, typically between 48 to 168 hours.
JTAG
The JTAG boundary-scan tests the PCB structure and its interconnecting wire lines without any external probing. The test uses powerful PCB boundary-scan hardware and software products to support applications such as flash and ISP programming, structural analyses, cluster functional test, and memory test.
A Functional Test
This test is often used by an electronics manufacturer to test that your PCB powers up. To carry out the functional test, external pieces of equipment and fixtures are required.
The electronics manufacturer either works with their client to design and develop the functional test and its parameters, or the customer sometimes provides it. The most important aspect of this test is that it must meet the standard requirements of the electronics manufacturing industry, including meeting IPC standards.
PCB Testing: Essential for retail-ready
That pretty much covers all the different types of PCB tests, but how important are they? They’re entirely essential. The sooner any faults or errors are identified in the manufacturing process, the faster, easier, and more affordable they are to resolve.
Testing provides manufacturers with an essential link between design, production, and testing teams so they’re all working towards the same goal: to produce reliable, retail-ready PCBs. At MIS, we aim to produce error-free products with deep testing, verification, and multi-step quality control.
Find Out More
Now you know how a reputable electronics manufacturer, like M.I.S Electronics, improves PCB production from custom design to testing to delivery, contact us about your product. We provide high-quality, error-free, retail-ready boards. Tell us about your project, and we’ll provide a no-obligation free quote. We look forward to working with you soon!