What are the main aspects of electronic component screening?

Date：2022-10-17 17:09:43Views：703

The testing and screening service of electronic components is also called the secondary screening of electronic components. In the selection of electronic components, attention should be paid to quality control, overall consideration, scientific selection, simplified design, reasonable use of the performance parameters of components, and play the role of electronic components. The components and parts shall be selected in a comprehensive way, reasonably selected according to favorable conditions, simplified circuit design to improve reliability, and derated use to improve reliability. If you are interested in the content to be covered in this article, please read on.

The purpose of electronic component inspection and screening inspection is to verify whether a batch of components are qualified, and the purpose of screening is to select the unqualified components from a batch of components. The screening items of electronic components mainly include:

1) High temperature storage

The failure of electronic components is mostly caused by various physical and chemical changes in their bodies and surfaces, which are closely related to temperature. After the temperature rises, the chemical reaction speed is greatly accelerated and the failure process is accelerated, so that defective components can be exposed in time and eliminated.

High temperature screening is widely used in semiconductor devices. It can effectively remove devices with surface contamination, poor bonding, oxide defects and other failure mechanisms. Generally, devices need to be stored at the highest junction temperature for 24-168 hours.

High temperature screening is simple and inexpensive, and can be implemented on many components. After high temperature storage, the parameter performance of components can be stabilized and the parameter drift in use can be reduced. The thermal stress and screening time of various components should be properly selected to avoid new failure mechanisms.

2) Power electric aging

During screening, under the combined effect of thermoelectric stress, a variety of potential defects in the body and surface of components can be well exposed, which is an important item of reliability screening.

Various electronic components are usually aged for several hours to 168 hours at rated power. Some products, such as integrated circuits, can not change the conditions at will, but can use the high temperature working mode to improve the working junction temperature to reach a high stress state. The electrical stress of various components should be properly selected, which can be equal to or slightly higher than the rated conditions, but can not introduce new failure mechanisms.

Power aging requires special test equipment, which is expensive, so the screening time should not be too long. Civil products usually take several hours, military high reliability products can choose 100 or 168 hours, and aerospace components can choose 240 hours or even longer.

3) Temperature cycle

Electronic products will encounter different environmental temperature conditions during use. Under the stress of thermal expansion and cold contraction, components with poor thermal matching performance are prone to failure. The temperature cycle screening utilizes the thermal expansion and contraction stress between extreme high temperature and extreme low temperature, which can effectively eliminate products with thermal performance defects. Common screening conditions for components are - 55 ℃ to+125 ℃, with 5-10 cycles.

4) Centrifugal acceleration

Centrifugal acceleration test is also called constant stress acceleration test. This screening is usually carried out on semiconductor devices. The centrifugal force generated by high-speed rotation is applied to the devices, which can eliminate devices with too weak bonding strength, poor internal lead matching and poor mounting. Generally, the centrifugal acceleration of 20000g is selected and the test lasts for one minute.

5) Monitoring vibration and shock

Monitoring electrical performance while conducting vibration or impact tests on products is often referred to as monitoring vibration or monitoring impact tests. This test can simulate the vibration and impact environment during the use of the product, and can effectively eliminate components with poor mechanical structure such as transient short circuit and open circuit, as well as find faults such as faulty soldering in the whole machine. Monitoring vibration and shock is an important screening item in highly reliable relays, connectors and military electronic equipment.

The above is about the screening of electronic components and parts organized by the core creation detection team. I hope it will be helpful to you. Chuangxin Testing is a professional testing agency for electronic components. At present, it mainly provides integrated circuit testing services such as capacitance, resistance, connector, MCU, CPLD, FPGA, DSP, etc. Specializing in electronic component function testing, electronic component incoming appearance testing, electronic component dissection testing, acetone testing, electronic component X-ray scanning testing, ROHS component analysis testing. Welcome to call, we will serve you wholeheartedly!