Basic You Should Know About BGA rework station

1、What is a BGA rework station?

It’s an equipment used to repair BGA (Ball Grid Array) which is a kind of chip packaging. For example, the south bridge chip of a notebook motherboard is a packaged BGA. If there is a defective problem in the production line, it is necessary to use this equipment for maintenance. When encountering the empty soldering of the south bridge and the north bridge, and the short circuit fault, this equipment is needed. All BGA rework must follow a basic principle. The number of thermal cycles that the bga package and bga pads are exposed to must be reduced, and as the number of thermal cycles increases, the possibility for thermal energy to damage the pads, the solder mask, and the bga package increases.

2、 How to use the BGA rework station?

When it is detected that a certain chip has a problem and must be repaired, a BGA rework station must be used. Chips are now widely used in almost every aspect of life, such as mobile phone circuit boards, north and south bridges on computer motherboards, and LCD TV motherboards. BGAs are characterized by small package size, enhanced functionality, increased pin count, high durability, strong electrical performance, and low cost.

BGAs have four-sided pins, comparable to QFPs, and both are soldered to the board using SMT solder. The difference is that at the bottom of the board, the single-row pin headers, such as gull-wing pin headers, flat pin headers, or retracted J-type headers, are changed to full or partial rows, with two-degree spacing used to distribute solder balls and pins, as a tool for interconnecting the chip package to the circuit board solder. A BGA rework station is a machine that reheats and re-solders mis-soldered BGAs. Laptops, cell phones, game consoles, and desktop motherboards are all repaired by BGA rework stations. Desoldering, SMT, and soldering are the three main steps of a BGA rework station.

3、 BGA rework station for desoldering

• For the BGA chip to be repaired, we need to select the nozzle to be used first. Then, the operator fixes the pcb main board on the best BGA rework station, locates the laser red dot in the center of the BGA chip, shakes down the SMT head, and finally determines the SMT height.

• The operator can set the soldering temperature first and store it for direct use during maintenance. When in use, the operator should switch to the disassembly mode first, click the repair button, and the heating head will automatically heat the BGA chip. When the temperature curve disappears, the suction nozzle will automatically pull up the BGA chip and then rise to the initial position. The operator can connect the BGA chip to the cartridge. At this point, the soldering is completed.

4、 BGA rework station for installation

1) After the tin removal on the pad is completed, the operator uses a new BGA chip or a BGA chip after tin planting. After that, the operator fixed the PCB board, and then placed the BGA rework station on the position of the pad.

2) The operator should switch the rework station to the SMT mode, the SMT head will automatically move down, and the suction nozzle will suck the BGA chip to the initial position. 

5、BGA soldering rework station

1) The operator first turns on the optical alignment lens and adjusts the micrometer. Then the X and Y axes are used to adjust the front and back sides of the PCB, and the R angle is used to adjust the angle of the BGA. The solder balls (blue) on the BGA and the solder joints (yellow) on the pads can be displayed in different colors. After adjusting until the solder balls and solder joints completely overlap, clicks the "Finish" button.

2) After that, the SMT head will automatically drop, place the BGA on the pad, and then heat it. When the temperature line disappears, the heating head rises to the initial position, and the soldering is completed.

Some people think that packaging chips is a process that requires a high level of technology to ensure the success rate of chip repair. However, now we have a BGA rework station that is high-precision, accurate, and easy to operate, and also allows beginners to easily operate chip packaging.