Engineers utilize a Ball Grid Array (BGA) circuit board to verify that the printed circuit board (PCB) and the chip are properly connected. To get more usage out of a BGA chip with an outdated hinge, companies may need to rebuild older ball joints. It’s common practice to scrape off the oxidized solder balls and replace them with new ones. Reballing BGA occurs most frequently in video graphics processors in gaming systems, portable computers, and desktop computers.
Due to their poor reliability (particularly in terms of solder joint failure) and the need for frequent maintenance during their service lives, VGCs have earned the nickname “unlucky” in the business world. Despite their advanced design, even the most modern BGA circuit chips will require reballing at some point.
Reasons Why a BGA Circuit May Need to be Rebalanced
The first issue is that it has been overused. Depending on how frequently the graphics chip is used, the BGA package may need to be reball after a few days of constant operation. As time passes, the solder on the printed circuit board could weaken, allowing the chip to move around. This means users may experience increasingly severe display issues with time.
In the event of a malfunction, BGA chips may need to be returned to the manufacturer for a new shipment. There may also be a need to upgrade the BGA components on a PCB chipset to support the new features of the software.
Overheating can also cause BGA chips to fail, which would require reballing. A solder ball may melt and spread across the board if temperatures on the chips were allowed to become too high. Regardless of whether or not there is a solder connection, solder can still trigger your system to freeze or crash.
Tools Typically Used for BGA Reballing
-
Soldering Iron as a Heating Device
One must use a soldering iron, a specialized hand tool when soldering. When soldering, metal is melted into the spaces between the printed circuit board and the transistors. Soldering irons, which are insulated both at the handle and the tip, are employed to join metal components.
-
Soldering Compound
Solder paste is commonly used to attach surface-mounted components to their designated pads on printed circuit boards. Therefore, it greatly simplifies the process of soldering and attaching electrical components.
-
Using Wire For Solder Removal
You can pick up a sheet of desoldering wire—copper wire ranging in gauge from 18 to 42, braided, and coated with Rosin Flux—at your local electronics outlet. This desoldering wire can be used to soak up solder and remove it from a connection.
-
BGA Chip Case
The primary use of this conventional chip holder is to make reballing easier.
-
BGA Chips Stencils
In order to hold Solder Balls in place, a Chip Stencil is a metallic sheet with many holes. The Soldering ball is made primarily of metal, so it can be heated rapidly using a hot air gun or BGA equipment, making the procedure faster and easier.
-
Solder Balls
Solder balls are tiny spheres used in surface-mount technology (SMT) to securely attach electronic components to circuit boards. Common uses for solder balls include connecting many chip packages on a single circuit board subsystem and attaching chip packages to a PCB.
Simple BGA Reballing Process
Although BGA reballing processes vary by company, there are several standard procedures that are always followed.
-
Deball the Device
Utilizing a syringe and a gloved fingertip, inject a water-soluble paste flux into the device’s balls. To get rid of solder balls, you need to use the right blade tip and/or temperature setting for the solder ball alloy.
You can use a solder wick to get rid of any stray solder and level the pads. Be careful not to sweep the braid across the base of the part, as this could damage the mask or lift pads.
-
Clean the Deballed Part
The flux residue on the deballed component’s base can be removed with isopropyl alcohol and a non-static-producing wipe.
-
Use Flux Paste
It’s important to check the device for damage, such as a scratched mask or raised pads. The bottom of the component should be covered with a paste flux that is water soluble. Using a gentle brush, spread to an even layer on the underside of the portion.
-
Put Preform Ball Side Up
A flat heat-resistant surface, such as a ceramic plate, is ideal for placing the preform with the ball side up. Verify if the preform’s patterns match those of the machine. Always use solder balls made of the correct solder alloy while assembling electronic components.
-
Carefully Place Gadget on Top of Preform
In order to reball a BGA, the device must be carefully placed on top of a preform while maintaining the correct pattern orientation.
-
Reflow
Put the preform and device “sandwich” in a reflow oven or other heat source. Verify that the right temperature has been set.
-
Get Rid Of The Preform
The preform should be taken out of the apparatus when it is still somewhat heated. Make sure you’ve transferred all the balls into the machine. Use a gentle brush and some water to clean. Check again for scratched masks and displaced padding.
-
Inspect the Reballed Device
Under magnification, inspect the Rebalanced gadget according to the criteria you’ve established.
