Talking about the repair of BGA

BGA Detailed Explanation and Rework Tips

1. Basic knowledge: BGA (Ball Grid Array Package) technology involves placing circular or cylindrical solder joints in an array on the bottom of the chip. Unlike traditional chip packaging, BGA packaging is unique in that its solder joints are completely hidden under the chip, which gives it the following advantages:

Higher density pinouts

Better electrothermal performance

Complex rework process

2.1 PBGA (Plastic Package)

Advantages: low cost, easy processing

○ Features:

• Melting point of conventional solder: 183°C for leaded type and 217°C for lead-free type.

Pay attention to moisture

2.2 CBGA

Advantages: moisture-proof, stable

○ Features:

High melting point solder balls (90% lead and 10% tin)

The diameter of the solder ball is 0.889mm

No solder residue.

[Analysis of the repair process]

1. Key steps of rework 3.1 Preparation for pretreatment - pay attention to the tip: the preparation at this stage will be directly related to the efficiency of the rework job!

Drying process (key link):

CRITICAL STEP: Be sure to thoroughly remove residual moisture from the chip and board

○ Operation Specifications:

After baking, the follow-up process is completed within 24 hours.

• Temperature-sensitive components, such as batteries and optical fibers, must be removed beforehand.

Protective measures:

The repair area must be protected within 10mm.

• Seal with 5-6 layers of high-temperature tape

• Focus on protecting radiators, capacitors and other components

Tool Configuration:

加热喷嘴选：BGA+2-5mm

Large PCBs need to be supported.

Preferred plate center support point

Do not rely on component support

3.2 Consideration of temperature curve setting Due to the influence of many factors on temperature, every repair operation needs to:

Prioritize the use of historical curve data

No data is required for field testing.

• Use the same rework plate as the test board

Fix the thermocouple drill hole to the solder ball.

Curve Type Selection:

A triangular tent curve is recommended.

• Heating rate< 3°C/sec

• Cooling rate<5°C/sec

○ Key control:

The bottom of the PCB is preheated to prevent deformation

• Comply with the melting point temperature

By rephrasing, the article:

1. The total score structure is more logical.

2. Highlight key points and improve reading fluency.

3. Simplify the expression of technical terms

4. Operation Tips: Key Reminders

5. Optimized the aesthetics of typography

If you would like to elaborate more on a specific aspect, please feel free to let me know your specific requirements.