Category Archives: Test/Inspection


Oct08
What Can an SPI (Solder Paste Inspection) Machine Really Do?

SPI stands for Solder Paste Inspection. If we’re talking about the actual inspection equipment, people usually add “machine” after SPI. But in most cases, when you mention SPI in an SMT factory, everyone just assumes you’re talking about the inspection … Continue reading

Jun26
What is Environmental Stress Screening (ESS)?

Environmental Stress Screening (ESS) is a method used to apply certain environmental and operational stresses—such as power on/off cycles, bias voltage, pressure, thermal cycling, and vibration—to new or repaired products (usually electronics or components). The idea is to expose hidden … Continue reading

Mar21
Electronic Product Burn-In and Run-In: What They Are and Their Pros & Cons

In the early days, when electronic component design and manufacturing were still in their infancy, burn-in (B/I) was widely used to screen out defective products. This process helped eliminate early failures before products reached customers, reducing the risk of complaints. … Continue reading

Jan16
Inspection Methods for BGA Solder Ball Wettability and Soldering Defects

This is a summary post aimed at providing some guidance to newcomers in the electronics assembly field on methods for analyzing the solderability of BGA (Ball Grid Array) solder balls. Workingbear decided to write this after seeing someone ask about … Continue reading

Sep05
Using 2D X-Ray to Diagnose BGA Solder Void Issues

This is an X-ray inspection image of an MCU’s BGA soldering that failed after reflow. The owner mentioned that the BGA package was not functioning, but when pressing on the MCU, it would temporarily work again. Since Workingbear didn’t have … Continue reading