Circuit Board Development Status And Testing Repair

- Jun 20, 2017-

    The domestic research on the automatic detection system for printed circuit boards began in the early 1990s and has just started. The research institutes that are engaged in this research are also relatively few, and because of the influence of various factors, the study of the automatic optical detection system for printed circuit board defects also stays at a relatively early level. Circuit Boards Because of the foreign printed circuit board automatic detection system is too expensive, and the domestic did not develop a true sense of the printed circuit board automatic detection equipment, so most of the domestic circuit board manufacturers or use a magnifying glass or projector to see Approach to check the side. As a result of manual inspection labor intensity, the eye prone to fatigue, high leakage rate. And with the electronic products toward the miniaturization, digital development, printed circuit board is also moving towards high density, high precision development, the use of manual inspection method, the basic can not be achieved. For higher density and accuracy of the circuit board (0.12 ~ 0.10mm), has been completely unable to test. Detection means of backward, leading to the current domestic multi-layer board (8-12 layer) of the product pass rate of only 50 to 60%.Circuit Boards

    1. The chip with the program 1. EPROM chip generally should not be damaged because the chip requires ultraviolet light to erase the program, so the test will not damage the program, but there are information: due to the production of the chip material If you do not have to be able to damage (mainly refers to the program), so as far as possible to the backup. 2.EEPROM, SPROM, and with the battery RAM chip, are easy to destroy the program. Whether the chip in the use of <tester> VI curve scan, whether it destroyed the program, has not yet been conclusive.However, colleagues in this case, or be careful, I have done a number of tests , May be a big reason: maintenance tools (such as testers, electric iron, etc.) caused by leakage of the shell. 3. For the circuit board with a battery chip do not easily remove it from the board. Second, the reset circuit 1 When installing a large - scale integrated circuit on a circuit board, it should be noted that the reset problem is correct. 2. Be sure to replace the device before testing, turn on and off the machine, and press the reset button several times.Circuit Boards

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