Mobile phone repair when replacement BGA integrated block should pay attention to what

Mobile phone repair when replacement BGA integrated block should pay attention to what

First to check the BGA chip with glue, if with glue, it is recommended with the wind whirling wind guns,

temperature adjusted to 300-350, wind 3-4 and soldering paste evenly on the chip, uniform slow blowing

can. (bga rework station)

If you do not take the BGA chip, relatively simple.

BGA positioning

The positioning of the BGA can according to your method:

1. Draw a line locating method: demolition

before the IC with a pen or a needle in the BGA-IC week painting line, remember directions, ready to sign

for welding to prepare.

2. Stickers positioning method: before removing the BGA-IC, first along the sides of the IC label paper on

the circuit board stick, edge alignment of the edge of the paper and the BGA-IC, with a pair of tweezers

compaction cement.

3. visual method

BGA removal

Removal of key points:

1. Recognize BGA chip placement should be followed on the chip put the right amount of flux, can prevent

dry blowing, and can help under the chip solder joints evenly melt, to observe whether will affect the

surrounding components

2. T2688 Motorola, Samsung did A188, Ericsson T28 amplifier and a lot of soft package of character. These

BGA-IC resistant high temperature difference, blowing the welding temperature is not easy too high (should

be controlled below 200 degrees), otherwise, it is easy to blow them bad.

3. before taking the BGA chip, we must remember the correct location and direction of the chip, and now a

lot of BGA chip is not the direction of the tag.

BGA tin tin operation

Points to note:

1. To remove the IC, it is recommended not to remove the IC on the surface of the solder, as long as not too

large, and does not affect plant tin plate can cope with, because for those soft package IC such as Motorola's

font, if with tin absorption line to absorb it, will cause inside the IC weld legs indent brown leather, resulting

in difficulty on tin), and then use the day the water wash.

2. Akira wind mouth to plant tin tin slurry make uniform heating slowly, slowly melting. When saw the

planting of tinplate individual holes have solder ball formation, indicating that the temperature has been

put in place, when should raise the air gun wind mouth, avoid the temperature continues to rise. Too high

temperature will make the tin slurry boiling, causing the failure of tin tin, serious damage to the IC.

3. If the ball welding blowing and found some ball size uneven, and even individual foot is planted on the tin,

first with paper cutter along the graft of tinplate surface will have large solder ball of the exposed part of the

clipper, reoccupy scraper will solder ball too full of solder paste and missing foot small hole, and then use

hot air gun to blow a can. If the ball size is not uniform, repeat the above operation until the ideal state.

Replanting, must be clean, dry the tin plate.