1, LCR measurement
LCR measurement is suitable for some simple circuit boards. There are fewer components on the circuit board. There are no integrated circuits. Only some passive components of the circuit board do not need to be returned to the furnace after the end of the chip. The LCR is used directly on the board. The device is measured and compared to the rating of the components on the BOM. Once there is no abnormality, the production can begin.
2, FAI first test
The FAI first test system is usually composed of a set of FCI software-led integrated LCR bridges. The BOM and Gerber products can be imported into the FAI system. Employees use their own fixtures to measure the first sample components, system inputs and inputs. The CAD data is checked, and the test process software displays the results through graphics or voice, thereby reducing the misdetection caused by the negligence of the personnel, which can save labor costs.
3, AOI test
AOI test, this test method is very common in pcba processing, suitable for all pcba processing, mainly through the shape characteristics of components to determine the welding problem of components can also pass the color of the components, IC silk screen inspection To determine if there are any wrong components in the components on the board.
4, X-RAY inspection
X-RAY inspection, for some boards with hidden solder joints, such as BGA, CSP, QFN package components, the first piece of production needs to be X-ray inspection, X-ray has a strong penetration, is One of the earliest instruments used in various inspection applications, the X-ray perspective shows the thickness, shape and weld quality of the solder joints, and solder density. These specific indicators can fully reflect the welding quality of the solder joints, including open circuit, short circuit, holes, internal bubbles and insufficient amount of tin, and can be quantitatively analyzed.
5, flying needle test
Flying probe test, flying probe test is usually used in some small-scale production of development nature. It is characterized by convenient test, strong program variability and good versatility. It can basically test all types of circuit boards, but the test efficiency is compared. 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 board are short-circuited, empty soldering, wrong parts.
6, ICT test
ICT test, ICT test is usually used on the models that have been mass-produced. The test efficiency is high and the manufacturing cost is relatively large. Each type of circuit board needs special fixtures, 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. It is also determined by measuring the resistance between two fixed points to determine whether there are short circuits, empty welds, wrong parts, etc. on the components on the circuit.
7, FCT function test
FCT function test, FCT function test is usually used on some more complicated circuit boards. The circuit board to be tested must be simulated after the completion of soldering, through some specific fixtures, simulate the actual use of the circuit board, put the circuit board In this simulated scenario, observe whether the board can be used normally after turning on the power. This test method can accurately determine whether the board is normal.