“The world’s first bidirectional GaN IC is an ideal power semiconductor, the ultimate in efficiency in size, weight, cost, and bidirectional power flow,” said Navitas CEO and co-founder Gene Sheridan at a press briefing.

The company introduced the Bidirectional GaNFast Power IC and the IsoFast Dual-Channel Isolated GaN Driver this week at APEC 2025 in Atlanta. When paired, the two devices can eliminate several bulky components used in typical two-stage converters.

“Put it all together, and we have an invention at the semiconductor level in the system level that is going to transform multiple multi-billion dollar markets, from solar and renewable energy to electric vehicle onboard chargers and roadside chargers to energy storage of all kinds,” Sheridan said.

Bidirectional power IC and IsoFast, a specialized gate driver. Adapted from images used courtesy of Navitas

From Two-Stage to One-Stage Conversion

The bidirectional IC’s single-chip design includes a merged drain structure, two gate controls, and an integrated, autonomous substrate clamp. The bidirectional switch converters (BDS) can handle current and voltage in both directions and can switch at any frequency.

The BDS can replace four devices used in a conventional two-stage design and functions as two back-to-back power switches. Sheridan explained that most power systems today have two stages: a PFC circuit connected to the AC grid and a DC-DC converter to deliver the desired voltage. This design includes bulky DC-link buffering capacitors.

“With bidirectional, two-stage converters are a thing of the past,” Sheridan said. “We’re eliminating that second stage completely,” adding that Navitas’ single-stage converters are low-cost, high-density, lightweight, easier to manufacture, and more reliable.

The single-stage bidirectional BDS can replace four components in a two-stage design. Image used courtesy of Navitas

The single-stage design reduces size, weight, and costs. Jason Zhang, vice president of engineering, illustrated the impact with two Tesla onboard chargers (OBC). The OBC using the traditional one-stage system was about five inches in height, whereas the OBC using a one-stage system was only about two inches high. The one-stage OBC was 30% lighter and took up less space in the EV.

Zhang also revealed the boards inside the OBC casing to demonstrate how the one-stage system eliminates bulky components and allows total surface mount.

Navitas bidirectional ICs in an OBC design. Image used courtesy of Navitas

Gates, Drivers, and Navitas’ IsoFast

Since a bidirectional switch has two gates to handle the voltage in both directions, it needs a special driver to control them. The drive must be able to handle high transient and high-voltage isolation conditions with signal integrity.

Navitas’ solution is IsoFast, a galvanically isolated, high-speed driver that can drive the GaN BDS ICs and similar GaN/SiC devices. IsoFast has four times higher transient immunity than existing drivers (up to 200 V/ns) and does not need an external negative bias supply.

IsoFast diagram. Image used courtesy of Navitas

A patented monolithically integrated active substrate clamp automatically connects the substrate to the source terminal with the lowest voltage potential. This eliminates a back-gating effect, resulting in high efficiency, reliability, and performance.

“This whole system is four times better than previous systems,” said Dan Kinzer, Navitas co-founder, CTO and COO. “It’s far cheaper. It can save lots of money to take out the extra circuits and extra components that other solutions need to deliver the same function.”

Can the IC BDS Transform High-Power Design?

Navitas’ Bidirectional GaNFast Power IC can potentially reduce the size and costs of essential renewable energy and EV devices by shrinking the number of components needed in two-stage designs.

“The entire first PFC stage disappears,” Sheridan stated. “The electrolytic capacitors, DC link capacitors disappear. It’s inherently soft switching, so we can really exploit that high-speed advantage, high-frequency advantage, and shrink the passive components around the system more dramatically.”

The result is 30% more power density, 10% improved costs and energy savings, and reduced size and weight.

“The future of our electrified planet is bidirectional energy flow,” Sheridan said. “All of this is enabled now by GaN BDS, IsoFast, isolated drivers, put together in single-stage converters inherently bidirectional with their energy flow.”