What aspects of component inspection? What tests do you usually need to do?

Date：2021-05-28 18:11:00Views：1572

First of all, it depends on what components are tested. Different component testing methods are different. For example, triodes, diodes, electrolytic capacitors, resistors, light-emitting tubes, etc. can be tested with a multimeter, and ceramic capacitors with small capacity can be tested with a capacitance meter. The detection of components is an essential basic work. How to accurately and effectively detect the relevant parameters of components and judge whether the components are normal is not a stereotype. Different methods must be adopted according to different components to judge whether the components are normal or not.

There are three main types of testing items for electronic components:

1.Routine test

Mainly test the appearance, size, electrical performance and safety performance of electronic components;

Basic parameters such as triode shall be tested according to the specifications of components, including appearance, size, Icbo, Vceo, Vces, HFE, pin tension, pin bending, weldability, welding heat resistance and other items. RoHS shall also be tested for some export products.

2.Reliability test

It mainly tests the service life and environmental test of electronic components;

According to the requirements of the user and the specification, test the service life of the device and various environmental tests, such as triode, and carry out high-temperature test, low-temperature test, moisture test, vibration test, maximum load test, high-temperature durability test and other tests;

3.DPA analysis

It mainly controls the internal structure and process of the device.

Such as triode, the main means include X-ray detection of internal structure, acoustic scanning monitoring of internal structure and packaging process, unsealing monitoring of internal wafer structure and size, etc. Among them, X-ray real-time imaging technology is increasingly widely used. It is favored by more and more electronic product manufacturers because of its non-destructive, fast, easy-to-use and relatively low cost. X-ray detection can be used to check the internal status of components, such as chip layout, lead layout, lead frame design, solder ball (lead), etc. For components with complex structure, the angle, voltage and current of the X-ray tube, as well as the contrast and brightness of the image can be adjusted to obtain effective image information.

Electronic components can be divided into two categories: components and devices. The quality of the test is generally measured with a multimeter, and the components are mainly checked according to their own characteristics. For example, resistance is to check its size according to the characteristics of resistance. Generally, resistance damage is due to the increase of resistance value. For devices, it is necessary to check in combination with the characteristics of the main components of the device. For example, the detection of diode is to detect the positive and negative characteristics of PN junction. Before preparing the components, it is best to list the required components according to the circuit schematic diagram. In order to ensure that there is no waste of time and reduce errors in the trial production process, and ensure that the finished device can work stably for a long time, it must also be screened and tested after all components are prepared.