PCB News - Powerful Repair Cheats for PCB Circuit Boards

In recent years, the degree of automation of industrial equipment has become higher and higher, so the number of industrial control boards in various industries has also increased. After the industrial control board is damaged, the high cost of replacing the PCB circuit board(as little as a few thousand yuan, as much as more) Ten thousand or several hundred thousand yuan) has also become a very headache for enterprises. Circuit board repair, as an emerging repair industry, is also developing rapidly. Most of the damaged PCB circuit boards can be repaired in China, and it can save 70%-80% of the cost compared with buying a new board, and the time used is much shorter than the time for a foreign board to be fixed. The following describes the basic knowledge of circuit board maintenance.

Almost all PCB circuit board repairs do not have drawings and materials, so many people are skeptical about PCB circuit boards repairs. Although various circuit boards are very different, the same thing is that each circuit board is composed of various integrated blocks, resistors, capacitors and It is composed of other components, so the damage of the circuit board must be caused by the damage of one or some of the components. The idea of circuit board maintenance is established based on the above factors. Circuit board repair is divided into two parts: inspection and repair, of which inspection occupies a very important position. The basic knowledge of repairing each device on the circuit board is tested, until the bad parts are found and replaced, then a circuit board is repaired.
Circuit board inspection is the process of finding, determining and correcting the failure of each electronic component on the circuit board. In fact, the entire inspection process is a thinking process and a test process that provides logical reasoning clues. Therefore, the inspection engineer must gradually accumulate experience and continuously improve the level in the process of circuit board maintenance, testing, and repair.
General electronic equipment is composed of thousands of components. During maintenance and overhaul, it will be very time-consuming and very time-consuming to find problems by directly testing and inspecting each component in the circuit board. difficulty. Then the check-in type inspection method from the fault phenomenon to the cause of the fault is an important method of inspection and repair. As long as the circuit board detects the problem, it is easy to repair. The following basic formulas for circuit board repair are summarized for everyone, which is convenient and practical.
An ordinary circuit board, the circuit combination is tens of millions
The appearance of components changes frequently, and character recognition is the key
Resistance and capacitance are the most common, and damage is also common
The resistance value of the resistance is easy to change, and the capacitance leakage is still leakage
Inductance transformer is a coil, simple test to see the on-off
Diode and triode, measure the positive and negative of the PN junction
MOS tube and thyristor, trigger test is the key
All of the above are discrete components, integrated circuits for many years
The analog device has an operational amplifier, and the virtual short and virtual terminals are used to judge
Optocoupler isolates the front and rear stages, and the damage is tens of millions
Digital devices are often seen, before 40 and 74 marks
There is also an analog-to-digital converter, which is very laborious to test
Don't forget ROM and CPLD, programming depends on the programmer
CPU, single chip microcomputer, timing judgment logic instrument
Various sensors, the probability of damage ranks first

The above is the introduction of PCB circuit board maintenance. Ipcb is also provided to PCB manufacturers and PCB manufacturing technology