Happy GaNuary from NXP! GaN’s Continued Acceleration for the 5G Infrastructure

Maintaining a lead in the shifting RF market requires continuous evolution, and that’s something that we at NXP do very well. Using process technology to create an edge, we’ve supported every generation of cellular and have routinely set new standards for performance.

LDMOS technology is a classic example – having maintained a competitive advantage for almost 30 years. They now enable the majority of the world’s cellular voice and data traffic every day in some of the harshest environments. NXP strives by anticipating change and optimizing for new cellular requirements. Our latest AirFast LDMOS technology is helping drive cellular forward by supporting a global standard, including LTE and 5G NR.

LDMOS is an ongoing technology and isn’t going anywhere anytime soon. LDMOS still demonstrates high power and efficiency in cellular, broadcast and narrowband applications – but it’s a mature technology that’s reaching the limits of its ability.

Gallium Nitride (GaN), on the other hand, is a much younger technology and shows great promise for future designs. See our Versatile GaN Solution for Various Markets device. GaN already performs with greater ease than LDMOS and offers room to expand over time. In the 5G infrastructure, where base stations present a very specific set of requirements, GaN becomes the clear choice for power amplifiers (PAs), which are essential components for base stations.

The PA Challenge

In the signal chain of a cellular base station, the power amplifier (PA) sits between the transmitter and the antenna. The PA takes the low-level RF signal coming from the transmitter and boosts its power to the level required by the antenna. Ideally, the PA boosts the signal without changing it, but imperfections in the PA can add unwanted distortion to the signal and reduce performance.

The PAs used for 5G need to do three things: They need to amplify signals to higher frequencies than with previous generations of cellular, operate within the same footprint, and they need to do this while using less energy.

LDMOS, which has been the go-to process technology for PAs for a long time, does struggle to meet these three 5G requirements. GaN meets the challenge head-on, with support for higher frequencies, lower power and smaller size.

Higher Frequencies

LDMOS works best at lower frequencies, especially below 3 GHz. For 5G, the higher frequencies now being used GaN is more efficient. GaN can handle a higher voltage in a much smaller area than comparable LDMOS devices and can power a much wider range of mmWave frequencies than standard silicon. GaN is already used for microwave transmission, which operates in an area of the mmWave spectrum close to where new 5G use cases will be. GaN also supports operation in the so-called C-band spectrum, between 3.7 and 4.2 GHz, which is being opened up for 5G cellular operation.

Lower Power

Energy efficiency is a key issue for power amplifiers. Base stations are some of the most energy-intensive pieces of equipment in the cellular network, and as much as 20% of the electricity used by a base station can be attributed to the PA. As a result, even small increases in efficiency can lower annual electricity bills and reduce the CO2 footprint of cellular communications.

Higher data rates and increased bandwidth increase power consumption, so each successive generation of cellular has needed more energy to run. This is especially true with 5G. According to a 2019 report from ABI Research, a typical 4G LTE cell site consumes somewhere between 6 and 9 kW, depending on the level of traffic (periods of high traffic consume more power). ABI estimates that a typical 5G base station, which will support 2G, 3G and 4G traffic, as well as 5G traffic operating in different bands between 700 MHz and 3.5 GHz, is likely to draw as much as 14 kW on average and up to 19 kW during peak load. Add to this the fact that achieving full 5G coverage will involve deploying many more small-cell base stations, and the amount of power required to support 5G goes up even more.

Smaller Size

To make the transition to 5G more cost-effective, the goal is to develop 5G solutions that fit in the same footprint used by present-day 4G solutions. This makes 5G’s functionality easier to deploy and less disruptive because this solution fits in the same space provided by the enclosure and more of the base station’s equipment can remain in place.

GaN supports high-frequency operation, with higher power density and higher efficiency than LDMOS. However, GaN does all this in a thermal package comparable to that used by LDMOS technology. Also, since one GaN device can support multiple bands, a single device can be used to cover a broader range of use cases, and lowers the overall cost of the deployment.

NXP’s Continued Big Investment in GaN for 5G

We’ve been involved with GaN since 2003, and now offer a complete portfolio optimized for cellular infrastructure operation. Our 48 V GaN discretely delivers high power density in a small footprint and supports multiband operation, high-frequency capability and high efficiency. A prime example is our versatile device – the A3G26D055N – a GaN solution that has an unmatched output to fill multiple frequency bands and can be used across various markets.

We believe that our recent decision to bring our GaN process in-house positions us for continued leadership in power amplifiers. Our new, state-of-the-art six-inch (150 mm) RF GaN fab in the United States is built specifically to support the needs of 5G operation. Our process experts in Chandler, Arizona, have optimized the GaN technology to meet customer requirements and simplify the interaction between the RF and digital-control portions of the design. Also, the Chandler GaN facility is the only one in the United States today that adheres to strict automotive quality standards for an added level of reassurance for 5G operation.

The Chandler GaN facility continues to enable close collaboration between the fab and the R&D team. This collaboration has helped expand our portfolio across all frequencies and power levels. Carefully planned upgrades and rollouts are expected to deliver even higher levels of efficiency, size and cost, with a focus on the delivery of linearized RF performance.

Our work in Chandler underscores our commitment to 5G and is another example of how we continue to build on our track record of leadership in RF process technology.

To learn more about the Chandler GaN fab and our continued work in 5G, visit www.nxp.com/RFGaN.

Check out our latest design resources on the web. NXP has implemented its own user interactive product guide, the RF Product Selection Assistant. NXP is giving customers the capability to browse our Macro RRH, active antenna systems and our industrial and consumer portfolios.