1. LCR measurement
LCR measurement is suitable for some simple circuit boards. There are few components on the circuit board. There are no integrated circuits. There are only some passive components. After the patch is completed, there is no need to return to the furnace. The LCR is used directly to the circuit board. The device is measured and compared with the rated value of the components on the BOM. When there is no abnormality, the official production can be started.2. The first FAI test
The FAI first test system is usually composed of a set of LCR bridges led by FAI software. The BOM and Gerber products can be imported into the FAI system. The employees use their own fixtures to measure the first prototype components. The CAD data is checked, and the test process software displays the results through graphics or voice to reduce the false detections caused by personnel negligence, which can save labor costs.
3. AOI test
AOI test, this test method is very common in PCBA processing. It is applicable to all PCBA processing. The welding problem of components is mainly determined by the shape characteristics of the components. It can also be checked by the color of the components and the screen printing on the IC To determine whether there is a wrong component on the circuit board.
4. X-RAY inspection
X-ray inspection, for some circuit boards with hidden solder joints, such as BGA, CSP, QFN packaged components, the first part of the production needs to be X-ray inspection, X-ray has a strong penetration, is One of the earliest instruments used in various inspection occasions, X-ray perspective can show the thickness, shape and quality of solder joints, and solder density. These specific indicators can fully reflect the welding quality of the solder joints, including open circuits, short circuits, holes, internal bubbles and insufficient tin content, and can be quantitatively analyzed.5. Flying probe test
Flying probe test. Flying probe test is usually used in some small batch production of development nature. It is characterized by convenient testing, strong program variability and good versatility. It can basically test all types of circuit boards, but the test efficiency is relatively Low, the test time of each board will be very long, mainly by measuring the resistance between the two fixed points to determine whether the total components of the circuit board have short circuits, empty soldering, and wrong parts.
6. ICT test
ICT test, ICT test is usually used on models that have been mass-produced. The test efficiency is high and the manufacturing cost is relatively large. Each type of circuit board requires a special fixture. The service life of the fixture is not very long, and the test cost is relatively high. The test principle is similar to the flying probe test, and the resistance between two fixed points is measured to determine whether there are short circuits, empty welding, wrong parts, etc. on the circuit components
7. FCT function test
FCT function test, FCT function test is usually used on some more complicated circuit boards. The circuit boards that need to be tested must be after soldering, through some specific fixtures, to simulate the real use scenario of the circuit board, and put the circuit board In this simulated scenario, observe whether the circuit board can be used normally after the power is turned on. This test method can accurately determine whether the circuit board is normal.