In the process of PCB copying, as the circuit board needs to be split, the IC and other components need to be removed to make a BOM list, and the bare PCB board from the split is scanned and copied. Therefore, in this process, The correct disassembly of the integrated circuit on the PCB board is also an important topic.
Not only in the PCB board copy process, is in the circuit maintenance, often need to remove the integrated circuit from the printed circuit board, and because the IC pins are more and more dense, it is difficult to disassemble, sometimes will damage the integrated circuit and circuit board. Here, we provide several accurate disassembly integrated circuit effective methods, hope to help you.
Tin suction disassembly method :The use of tin suction device disassembly integrated block, this is a common professional method, the use of tools for ordinary suction, welding dual-purpose electric iron, power above 35W. When removing the integrated block, just place the heated dual-purpose electric soldering iron head on the pin of the integrated block to be removed. After the solder joint is melted and sucked into the fine tin, the integrated block can be removed after the solder of all the pins are sucked.
Medical hollow needle disassembly method :: Take medical 8 to 12 hollow needle several. When used, it is appropriate that the inner meridian of the needle just covers the pin of the integrated block. When disassembling, melt the pin solder with the soldering iron, cover the pin with the needle in time, then remove the soldering iron and rotate the needle, and pull out the needle after the solder solidifies. This allows the pin to be completely separated from the printed board. Once all the pins have been done this way, the block can be easily removed.
Electric iron brush with disassembly method: This method is simple and easy, as long as there is a electric iron and a small brush. When disassembling the integrated block, the electric iron is heated first. When the soldering tin on the pin is melted at the temperature of dissolving tin, the dissolved solder is swept away with the brush. This separates the pin of the block from the printed board. The method can be carried out separately or separately. Finally, pry off the block with pointed tweezers or a small "one" flathead screwdriver.
Add solder melting disassembly method: This method is a convenient method, as long as to add some solder to the pin of the integrated block to be disassembled, so as to connect the solder joints of each column of pins, so as to facilitate heat transfer and easy disassembly. When disassembling, each row of pins heated by electric iron should be pry with pointed tweezers or small "one" flat-head screwdriver. The two rows of pins should be heated alternately until removed. In general, each column of pins can be removed by heating twice.
Multi-strand copper wire tin removal method: is the use of multi-strand copper core plastic wire, remove plastic skin, the use of multi-strand copper core wire (can use short wire). Before use, put the rosin alcohol solution on the multiple strands of copper core wire. After the electric soldering iron is heated, put the multiple strands of copper core wire on the integrated block pin for heating, so that the tin welding on the pin will be absorbed by the copper wire, and the part that absorbs the solder can be cut off. Repeat several times and all the solder on the pin can be sucked away. Braided wire in shielded wire can also be used if possible. As long as the solder is sucked up, gently pry with tweezers or a small "one" screwdriver, the integrated block can be removed.
Metro equipment VS core technology localization
The so-called localization, in fact, contains two contents: first, important equipment to achieve domestic manufacturing production, or import foreign parts domestic assembly, some foreign companies set up enterprises in the domestic production of assembly equipment also belongs to this category; Second, we need to achieve independent innovation in key and core technologies. This localization, also known as autonomy, is actually a deep goal pursued by localization.
The localization of the former equipment, under the leadership of a group of excellent reverse engineering enterprises such as Loongson Century, has improved the overall domestic production rate through technical services such as PCB copying board, complete machine cloning and secondary development. For example, the Dalian Metro, which is under preparation, has 100% domestic heating and ventilation in its mechanical and electrical equipment. The localization rates of power supply system, vehicle purchase and safety door are 93%, 80% and 70% respectively. The localization of the latter core technology has always adopted foreign technology due to the lack of independent innovation. For example, in terms of signal systems, Siemens technology is used in Nanjing and Guangzhou subways, Casco Signal Co., Ltd. is used to serve Shanghai Metro Line 10, and Ansaldo (USA) International Co., Ltd. is used in Hangzhou Metro, although their signal equipment is domestically produced.
Measures to improve the localization of core technologies
Aiming at the situation that domestic production of our subway equipment is popularized and the core technology is lacking, we should encourage independent innovation, integrated innovation and the assimilation and absorption of introduced technology to improve the technological level of our urban rail transit equipment. The independent innovation in a long period of time is a risky and arduous way, so according to our national conditions, can be adopted by some companies with larger strength. However, the introduction of technology digestion and absorption can be used in any enterprise, but also in a short time to improve the country's re-innovation height. As an important means of introduction and absorption, Loongson PCB copying board can not only extract a full set of technical data such as PCB file, BOM list and SCH schematic diagram of foreign products, but also re-develop the core technology through on-board chip decryption, program disassembly and PCB board modification.