Navitas Technology Takes GaN to New Power Heights
A new and improved GaN technology is moving from the cell phone charger market into higher power, high-reliability applications. EE Power spoke with Navitas’ Stephen Oliver to find out how, and we’ve got everything engineers need to know.
Forty years ago, silicon chips powered the digital revolution. Now, silicon is “long in the tooth,” Stephen Oliver, Vice President of Corporate Marketing and Investor Relations for Navitas Semiconductor, told EE Power.
Navitas’ GaNSafe power IC is designed for data centers, solar storage, electric vehicles, and other high-power, high-reliability applications. Image used courtesy of Adobe Stock
“There are two new kids on the block,” Oliver said, referring to silicon carbide (SiC) and gallium nitride (GaN), two chemical compounds quickly replacing the outdated technology of yesterday.
In fact, Yole Group estimates that will happen by 2028, which Oliver calls “tomorrow” in engineering estimates.
”Over 30% of the original silicon market will have been eaten by a combination of GaN and silicon carbide,” Oliver contended. “So we're really at the start of this adoption curve of these new materials. And these new materials are basically more advanced versions further along the periodic table. They do things better than the old silicon chip. They make power systems better, faster.”
That’s exactly what Navitas has achieved with the GaNSafe power IC, the newest addition to its GaNFast product line designed for use in data centers, solar inverters, electric vehicles, and other high-power, high-reliability applications.
The GaNSafe wide bandgap power platform is designed to “break through the glass ceiling into higher-power applications,” Oliver promised and explained in the video below.
Video provided by EEPower
The GaNSafe Story
GaN has been used in consumer electronics like cell phone and laptop chargers. But when transitioning the technology from 60 watts for cell phones to 3,000 watts for a data center and 6,000 watts for an electric vehicle, GaN chips must be bigger, having more resistance to handle more power.
The Navitas chip is six times bigger, two and a half times thicker, and housed in a bigger package (a 10-millimeter box instead of five-by-six) to manage these challenging applications.
“We needed to make the package three or four times bigger, but also strong so that it can survive mechanical fatigue,” Oliver explained, noting the drastic weather changes EV chargers are exposed to. “It shakes, it rattles, it rolls. And it gets hot and it gets cold. So we needed to make a really physically robust and physically larger device.”
Enclosed in a TOLL (Transistor Outline Lead-Less) packaging, the GaNSafe technology is protected from extreme temperature changes and tough operating conditions, up to 22,000 W.
The Road to Higher Power and Higher Reliability
Protecting the gate is complicated and takes away from the efficiency and speed gains of discrete GaN technology.
“You can put extra components around it to try and regulate and control the voltage, but that means you've got more components on the board. And also, it means more points of energy loss,” Oliver explained, rattling off a list of drawbacks. “You've got more cost because of these extra components, more complexity in how to design it. And to avoid these spikes, you actually have to slow down the way the system works.”
And that's a big problem. Why?
“Because GaN is a racehorse, it wants to run at top speed, and in power electronics, speed shrinks things down,” Oliver explained.
If the main transformer inside an electric vehicle or a solar inverter runs at high speed, the faster it goes, the smaller, lighter, and cheaper the transformer gets.
“But if you've got this discrete device, only the switch with the gate hanging in the wind, you have to slow everything down so it doesn't get destroyed,” Oliver continued. “You may as well go back to the old silicon chip. Because you're not using the technology and its advantage.”
Solving the Issues
So, how did Navitas solve these issues? By protecting the gate that’s “hanging in the wind” and causing voltage spikes that can damage the device.
As Oliver explains in the video below, better protection means faster and more reliable performance.
Video provided by EEPower
“We actually put many different functions and features inside our chip because we have the ability to integrate using GaN material. And we're the only company in the world that has high-voltage GaN power. It runs at high speed. It's very efficient,” Oliver contends. “And with that, we can run it to megahertz, two million cycles per second. Reliably. As that weak gate is completely, carefully controlled inside our chip, you can't get to it from the outside world.”
Ultimately, Navitas is the only company integrating GaN on one chip – a challenge facing the competitive landscape.
GanSafe uses an integrated circuit. Image used courtesy of Navitas
Compared to silicon-based technology, GaNSafe can be customized for specific uses – for example, electric vehicles and next-gen data centers.
For EVs, GaN speeds up charging time, alleviating the anxiety associated with battery range and how long it takes to charge.
With a GaN-powered charger, a battery charges from 10% to 80% in 18 minutes. At the same time, GaN allows discharging power from the car battery back to the house, if necessary.
“Let’s say you live in New England, and you get an ice storm. A tree falls down, takes out the power line outside the house. You’ve got a bunch of energy sitting in the car,” Oliver said. “With GaNSafe, it’s possible to discharge power from the battery back to the house and keep the refrigerator or the WiFi going.”
In addition, the single GaNSafe chip can handle the 400 volts needed for the main EV battery while adjusting for the low 12 V needs of the radio or interior lights.
“So this one box charges the car,” Oliver said, “It can charge the house and also power your radio. “And it’s smaller and lighter and more efficient than doing it with the old silicon chip.”
Next-Generation Data Centers
The explosion of artificial intelligence is putting a strain on data centers.
“Think of these big warehouses with lots and lots and lots and lots of cabinets of computers inside,” Oliver described.
Now imagine that GaN technology replaces the silicon chips.
Data center servers. Image used courtesy of Adobe Stock
“It delivers more power in a very small space than with the old silicon chips, which is good because imagine one of these filing cabinets full of computers. In the past, they used to take about 30 or 40,000 watts of power to run,” Oliver explained. “Now, we're talking about 100,000 watts, in the same cabinet. And we're not being given more space to do that.”
Compared to silicon technology, GaNSafe requires one-third fewer parts and represents a 40% reduction in size while increasing efficiency to 96%. It can consistently process up to 3,200 W versus 2,800 W in conventional technology and requires less energy for cooling.
Solar and Storage
As solar energy use grows, efficient inversion and storage becomes critical.
As solar inverters convert DC power from the solar panel to AC that is fed into storage or the grid, efficiency, reliability, and size are key to ensuring the highest level of power delivery and fastest return on investment.
GaNSafe is engineered to endure the intense heat and solar radiation that cause other technologies to fail.
GaNSafe increases the efficiency and reliability of solar inversion, whether to send it back to the grid or into battery storage. GaN also saves energy by decreasing the need for cooling.
In addition to the many benefits of GaNSafe technology, it offers predictability for designers.
“We basically use this technology to make a designer's life easy. We want the designer to be able to sleep at night,” Oliver said in conclusion. “The designer is looking for predictable behavior, and whether it's a cell phone or a washing machine motor drive, or something higher power, predictability is key. Specifically, in these higher power markets.”
EE Power Editor Karen Hanson and EE Power Editor-in-Chief Barbara Vergetis Lundin co-authored this article.