Metody wykrywania uszkodzeń PCB

Istnieje kilka sposobów wykrywania awarii PCB. Wśród tych metod są promieniowanie rentgenowskie, analiza wycinków i mikroskopia optyczna. Każda z tych metod jest przydatna do identyfikacji i oceny stopnia uszkodzenia PCB. Jednak nie wszystkie z tych metod są odpowiednie dla każdej awarii PCB. Na przykład, uszkodzenia spowodowane wyładowaniami elektrostatycznymi są trudne do wykrycia. Wpływa ono na komponenty poprzez zmiękczenie lutowia i powodowanie wielu zwarć. Aby uniknąć tego problemu, należy dokładnie monitorować proces produkcji.

X-rays

PCB X-rays are a useful tool for detecting PCB failures. These images can reveal problems such as voids and solder traces. These problems can occur due to escaping gases or overheating of solder.

Slice analysis

Slice analysis is a method used to analyze the microstructure of PCBs. It can help detect a wide variety of PCB failures. Slice analysis involves cutting the PCB into vertical and horizontal sections and examining their cross-sectional characteristics. It can identify many different PCB failures, such as delamination, bursting, and poor wetting. This information can be useful for quality control in the future.

Optical microscopy

Optical microscopy can be an effective method for detecting PCB failures. It provides detailed images of the failure sites, and it can be used to detect nonconformities and identify contamination sources. The method is also useful in documenting samples as they are received.

ALT

The ALT method for PCB failure detection is a more direct approach to measuring solder joints and solder paste deposition. This technology uses a laser beam to scan a PCB assembly and measure reflectivity of various components. The measured value is then compared to a board’s standard specifications to determine if there are any faults.

Micro-infrared analysis

PCB failures are typically caused by defects on the solder joints. By determining the cause of the defect, manufacturers can take necessary steps to prevent recurrence. These measures may include eliminating solder paste contamination, making sure that the PCB has the correct aspect ratio, and minimizing PCB reflow time. There are a variety of methods used to analyze PCB failures, ranging from simple electrical measurements to analyzing sample cross-sections under a microscope.

ALT measures solder joint deposition

ALT (Aligned Light Transmitter) is a newer technology for measuring the height and shape of solder joints and solder paste deposition on PCBs. This technology is more precise and allows for a fast measurement. The ALT system uses multiple light sources, such as cameras or programmable LEDs, to illuminate the solder joint components. The amount of light reflected from each component is measured using the power of the beam. However, secondary reflection can cause an error in measurement, since the beam may reflect from more than one position.

Wyładowania elektrostatyczne

The Electrostatic Discharge (ESD) method is used to detect PCB failures. An ESD is the result of extreme electrical stress, which can cause catastrophic failure and hidden damage. It can occur for a variety of reasons, including high current density, an increased electric field gradient, and localized heat formation. The resulting damage is hard to detect and can cause major product failures. PCB assemblies are most susceptible to ESD when they are in contact with other charge-carrying objects.