Quite often after repairing the phone you can see in the check for repair wording of this type “made a replacement for the microcircuit of the phone.” As a rule, the price for such work goes out a lot. But at the same time the client does not usually know the process of this work on the chip soldering (chip), and even if he does, he does not understand everything to the end.
Let’s look at the BGA-type chips – this is the most common type, and the vast majority of mobile phone manufacturers use it. So, the memory chip itself in this chip is the most common reason that a mobile phone overtakes “sudden death”. Even there is such a term “Sudden death syndrome”. This is the main drawback of these chips.
A wide range of phone manufacturers uses these chips in their models (htc, samsung, huavei and others).
What sequence of works is used to diagnose such a malfunction and subsequent electronics repair. Let’s look in order:
First and foremost, the mobile phone card itself undergoes a close visual examination. It is checked whether there are cracks on the compound layer (polymer composition, which the manufacturer covers the chip). Is there rust on the elements and contacts, visual defects and visible board malfunctions.
Although it seems easy and fast, however in practice, it is quite a lengthy process, which is carried out necessarily by a qualified specialist with the necessary knowledge and experience, and if there is a special. equipment (for example, an engineering microscope).
After that the next stage of diagnostics is going on – the monitoring of the current consumption of the mobile phone’s circuit board is carried out.
If, after these diagnostic steps, the specialist decides that the cause of the failure of the phone is a memory chip, then it decides to replace it.
How is the chip replaced.
First of all, the chip compound is cleaned all around the perimeter. This is necessary in order that when the chip is subsequently dismantled, it is not accidental to damage the electrical connections of the circuit elements standing next to each other.
Next, the memory chip itself is removed, with the help of special equipment. Remains of the compound are cleaned, contacts are cleaned and soldered at the connection points of the microcircuit and the phone card.
Then the master prepares a new microcircuit for installing it on the board. Produces the necessary rations, and then mounts it directly to the board.
It’s no secret that for such operations, maximum care and accuracy of specialists is required, since the work requires jewelry accuracy.