LGA vs. BGA: How They Differ

This article is an LGA vs. BGA comparison.

One of the most critical joints to be keen on when assembling a computer is the CPU-to-motherboard connection.

Modern PCs have tiny, powerful chips, with most implementing SMT LGA or BGA packaging. 

The two are surface-mount packaging options, and we’ll compare LGA vs. BGA to see the best application for each.

Let’s get right into it!

What Is LGA?

LGA is short for Land Grid Array. It is a surface-mount technology type for chips (integrated circuits) with pins on the CPU socket.

So the pins emerge from the motherboard, while the chip has flat contact pads.

The name “grid” comes from the arrangement of the pads on the chip because they form a grid pattern.

When you insert the chip into the socket, the pins contact these pads to establish electrical and signal connections.

It is worth noting that some PCBs or motherboards lack LGA sockets for these chips.

In such a case, the only way to attach the two is by soldering the chip to the board.

LGA is more closely related to PGA (Pin Grid Array) because the two are mirror opposites.

PGA features pins on the processor chip and contact pads on the motherboard socket.

Two PGA CPUs

Advantages of LGA

• Easy to install/remove (requires no soldering)
• Pins provide better mechanical support than BGA solder balls
• Easy to inspect and test the connection pins
• Durable pins
• Cheaper to make

Disadvantages of LGA

• Although the pins are durable, damages can occur and are expensive to fix
• Limited heat dissipation (contact pins reduce the surface area for thermal transfer)
• High solder joint fatigue when soldered (caused by vibrations, thermal cycling, etc.)
• Limited pin density (pins occupy more space than solder balls)
• Consumes more power

LGA Applications

LGA packages come in different pin configurations differentiated by socket types. They include the following.

• AMD Ryzen Threadripper (LGA socket TR4)
• AMD Epyc (LGA socket SP3)
• AMD Ryzen Threadripper 3000 series (LGA socket sTTRX4)
• AMD Ryzen 7000 series (LGA socket AM5)
• Intel 6th – 9th gen processors (LGA 1151 – socket 4)
• Intel 10th – 11th gen processors (LGA 1200 – socket H5)
• Intel 12th – 13th gen processors (LGA 1700 – socket V0)
• DDR4 memory modules (LGA 3647 – socket P, P0, and P1)
• Power MOSFETs, such as Infineon OptiMOS
• Intel I210 ethernet controller

An LGA CPU

What Is BGA?

Like LGA, BGA (Ball Grid Array) is a surface-mount packaging technology, but the connection is different.

Instead of using pins, BGA relies on tiny solder balls arranged in a grid (rows and columns). 

A BGA integrated circuit

Usually, these solder balls reside on the semiconductor chip.

So the PCB or motherboard has solder pads to match the location of the balls.

But in some cases, it might be the opposite.

BGA connections don’t use sockets; you must solder the chip to the board.

But before mounting, you can assemble the balls manually or automatically. And using tacky flux simplifies the assembly process.

Once the balls are in place, place the chip above the mounting pad.

You can use infrared heaters or reflow ovens to melt the solder to create mechanical and electrical connections.

Types of BGA

BGAs come in the following types.

Plastic Ball Grid Array (PBGA)

These BGAs have Bismaleimide Triazine as the core substrate material and can contain 200-500 balls.

They are typical in dual-sided circuit boards.

Ceramic Ball Grid Array (CBGA)

This BGA has a high melting point because it has a ceramic substrate with Tin and Lead in the ratio of 10:90 (Tin: Lead).

This factor implies better thermal conductivity and reliability.

Also, it has a high ball count, and you can get even more contact points if you use CCGA.

CCGA (Ceramic Column Grid Array) uses solder columns instead of balls, which close to doubles the contact points.

A circuit board with a BGA socket

Flip-Chip Ball Grid Array (FC-BGA)

This BGA is similar to CBGA but uses a BT resin substrate instead of ceramic to save on costs.

Also, it has a different Tin: Lead ratio (63:37), better conductivity, and shorter electrical pathways. 

Another advantage of PC-BGA is you can realign the chip without using a flip-chip alignment machine.

Enhanced Ball Grid Array (EBGA)

EBGA is a modified version of PBGA that has additional heat sinks for better heat dissipation.

The package places the chips facing downward with a wire bond between the board and chip for conduction.

Tape Ball Grid Array (TBGA)

TPGAs have superb electrical and heat conductivity properties because they feature flexible interconnects for creating fine lines on the balls. However, the technology is expensive.

Metal Ball Grid Array (MBGA)

These BGAs have a metal-ceramic substrate with wire bonding to create the connections.

Like TBGA, MBGAs have excellent electrical conductivity and heat dissipation properties.

Micro BGA

These miniaturized BGAs feature packing tape substrates on down-facing chips.

Their primary advantage is they use an elastomer between the chip and tape.

This material enhances the connection’s ability to handle stress caused by thermal expansion.

And the low number of pins makes this BGA ideal for high-storage products.

Advantages of BGA

• Tiny, space-efficient package (ideal for mobile computing devices)
• Efficient heat dissipation
• Low impedance due to the short lead connection path
• Easy to unsolder and rarely experiences damage
• Reballing and deballing are possible
• Reliable mechanical and thermal properties
• Highly portable among different devices

Disadvantages of BGA

• Requires soldering equipment to mount on PCBs/motherboards
• Solder inspection can only occur using X-rays
• Only usable on multi-layer PCBs
• Difficult to repair (requires special skills and equipment)

A BGA rework station

BGA Applications

Some BGA component examples include:

• Field-Programmable Gate Arrays (FPGA), such as the Xilinx Virtex UltraScale+
• Most GPUs, such as Nvidia GeForce RTX 3090
• Memory controllers like the Cypress HyperBus
• SoC (System-on-Chip) processors like the Qualcomm Snapdragon 888

LGA vs. BGA: Pitch

Pitch refers to the distance between the center of each ball, pin, or contact pad to the next.

BGAs have a tinier pitch than LGA, enabling them to pack more balls on a smaller surface. The higher ball density enables more connections per area.

LGA vs. BGA: Installation

All BGA package types require soldering when mounting on a board. On the other hand, PCBs with LGA surface mount pins usually have a socket to lock in the chip. So installing LGAs is easier.

A technician installing a CPU in an LGA 1155 socket

But it is worth noting that some LGA connections require soldering. But generally, most have PCB or motherboard sockets.

LGA vs. BGA: Reparability

LGA contact pins are highly durable. But in case they break, repairing them is a challenging and expensive task.

But luckily, the pins are on the board. So there is no chance you’ll damage the chip.

On the other hand, BGA balls are easy to recall, deball, and unsolder.

But soldering the chip to the board or inspecting/repairing the package is challenging.

A silver holder for BGA reballing

Remember, the balls reside under the chip, hidden from view.

So you’ll have to use an X-ray machine for inspection and a hot air gun for removal.

LGA vs. BGA: Thermal Properties

BGA packages tend to have better thermal properties than their LGA counterparts.

The solder balls create an efficient and uniform heat transfer path from the chip.

A 3D model showing the temperature distribution under a BGA chip

LGA vs. BGA: Cost

BGA surface-mount packages are more expensive to build than LGA packages because they have an additional solder ball mounting process.

LGA vs. BGA: Size

BGA packages are more compact than LGAs because of the short pitch between the balls.

This factor explains why the mounting technology is ideal for portable devices like mobile phones and laptops.

But large devices like desktop computers use LGA packages because space is not an issue.

The mounting technology is cheaper to build, so it makes sense to use LGA.

LGA vs. BGA: Mechanical Stability

LGA packages offer better mechanical support because the motherboard socket has a locking latch to secure the chip.

So the chances of damage when transporting or handling (repairing) the device are low.

An LGA 1200 socket

LGA vs. BGA: Signal Integrity

The balls in BGA packages create shorter interconnect lengths that reduce the parasitic capacitance and inductance.

These properties minimize noise and enhance signal integrity.

Differences Summary

Which Is Better? – Conclusion

There is no obvious winner from the two because each chip mounting package has unique pros and cons.

So consider these factors to determine the most appropriate technology you will use in your device.

For instance, if building a desktop PC, look for an LGA-based desktop motherboard.

And it should have a compatible motherboard socket for your CPU.

But if building a laptop or mobile device, get a BGA-based CPU and motherboard.

This setup will enable you to create a compact circuit with a high component density for your project.

That’s it for now! We hope the article has been insightful.

Comment below to let us know your sentiments or what you want us to cover next.