September 24, 2022
iPhone logic board repair is generally the repair of chips and board layers on the motherboard, which is divided into two technologies:
Generally, if it is bumped, water enters, or is charged with a high copy charging device, it may lead to virtual welding, short circuit, electric leakage, and circuit breakage of the baseband of the iPhone.
If you get the above situation, after eliminating the battery problem first, you need to use a multimeter and some related current equipment to detect and determine which area of the motherboard is short-circuited or leaked. Since there are thousands of chips on the motherboard, even if a local area is detected, it is impossible to determine which or which chips are faulty. This requires the rosin detection method. The steps are:
1. Smoke a layer of atomized rosin on the detected short-circuit area of the motherboard.
2. Then power on the motherboard and test it.
3. The flux rosin press on the short-circuited chip will melt immediately, revealing black color.
The chip under the melted rosin is the short-circuit chip, and then the short-circuit chip is replaced by the chip transplantation technology. The steps are:
1. The air gun heats the nickel around the short-circuit chip to dissolve it. (The temperature control is in place, otherwise it is easy to burn the nearby chips)
2. Carefully remove the short-circuit chip.
3. Solder the new chip by repair welding. It also needs to be heated by an air gun and then cooled.
The process is a skillful job and requires a certain amount of technical experience. In some cases, it is found that the capacitor is short-circuited, and the capacitor can be removed directly.
If the circuit of the board layer is broken or short-circuited, it needs to be motherboard repaired by the technology of flying wires.
Through these two technologies, the motherboard can be repaired and the boot can be used normally.
November 17, 2022 0 Comments