LGA rework is a highly technical process that necessitates the use of specialized methods and abilities. For LGA components to be properly reworked, the solder paste must be accurately printed onto the PCB land regions. You’ll require engineers who are familiar with the way apertures and stencils are designed for LGA harvesting service.
Overview of LGA
Soldering wireless modules using LGA technology gives the most reliable and versatile surface mounting technology. Customers may choose their own solder paste, varying degrees of overprinting, and exact soldering results thanks to LGA modules’ improved circuit footprint and pad size.
- Reduced footprint and pad arrangement
Due to the unique pad configuration, warpage effects are eliminated during reflow processing by removing pads from the center and corners of the module.
- Enhancement of conductivity
The NiAu surface minimizes passivation concerns and boosts conductivity and performance when storing and soldering.
- Reduced interference along the antenna’s route
The influence on the antenna path is reduced by the use of ground pads beneath the RF components.
- Customized overprinting
Custom overprinting with a high yield rate and optimal performance is possible because of pad size and level pitch flexibility.
Ball Grid Array (BGA)
“Ball Grid Array” is the acronym for the term “BGA.”. The connections in this package are created with tiny solder balls placed in a square grid on the chip’s bottom surface. Compared to PGA, this architecture allows for twice as many connections to be accommodated. The solder balls allow for high-speed contacts, resulting in a massive performance.
BGA’s benefits include a tiny footprint, good heat dissipation, and low impedance because of the short circuit board connecting routes. It is also possible to remove the chips without hurting them.
This allows for the replacement of old solder balls with fresh ones. A new circuit board can then be created by soldering the chip into place. BGA is most commonly utilized for embedded CPUs because soldered processors are physically and thermally more durable.
Due to the connections being covered and difficult to reach, only X-rays can be used to inspect the solder joints. As a result, just a few repair choices remain. For safe soldering, a so-called reflow oven is necessary. On top of that, BGA chips may only be utilized successfully on multilayer boards, which restrict their application range.
Is it better to utilize a BGA or an LGA?
LGA technology provides greater flexibility for mass production and smart manufacturing while maintaining the simplicity of use of both automatic pick and place and automatic soldering.
Flexibility
- BGA – To secure the solder balls to the module, heat must be applied. Precision is required while using the soldering paste to fit solder balls already on the module. Solder paste selection is limited for customers due to the previously established solder’s temperature profile.
- LGA – Solder pastescome in various forms, making it possible for customers to customize the soldering process to meet their specific requirements. Blank pads allow customers to customize their own solder paste.
Durability
- BGA – To secure the solder balls to the module, heat must be applied. As a result, the coplanarity and functionality of BGA chips are reduced by as much as 50%. During module manufacture, further heating is required to secure the balls to the module’s ground.
- LGA – LGA pads are arranged in a way that maximizes heat dissipation. Near the corners and in the center, connections would be crucial. NiAu pads prevent surface corrosion. Soldering junctions are affected by limited PCB warpage.
Reliability
- BGA – Passivation of the balls is caused by flux residues, which reduces their conductivity. Module yield rates might be adversely affected by flux residues on the ball surfaces of the modules.
- LGA – Customer-specific overprinting is possible thanks to an optimized pad size. The user-friendly flat design makes it easier for customers to get the most out of the product. The placement of the pads helps to keep the RF component as unaffected as possible. In order to keep the RF components in place, ground pads are affixed to the chassis.
The Benefits of LGA Rework and Repair
Reworking the LGA can be difficult and time-consuming. Allowing the engineers to take care of the work will increase your productivity and lower your costs. They are BGA rework specialists that have the skills and expertise to execute your project according to your specifications.
An effective rework can help you fulfill deadlines and produce high-quality items. It is common for LGA rework to need board solder mask repair and the bonding of new PCB pads.
To assure the dependability and integrity of the rework, use PCB Services that have the knowledge and equipment to perform the task and check it thoroughly using X-ray and endoscopic capabilities.
Untrained engineers might easily make mistakes when doing LGA rework because of its specialized and technological nature. The inappropriate equipment, insufficient preparation, faulty techniques, and other factors can cause problems during production. Among the most common issues is excessive voiding of solder joints, incorrect BGA positioning, and damage to the pads during the removal of the BGA.