GaN vs Silicon: The Next Semiconductor Revolution in Power Supplies

Power electronics is undergoing a fundamental shift. For decades, silicon-based semiconductors have been the backbone of power supplies and battery chargers. But a new material is redefining what is possible in performance, size and efficiency:

Gallium Nitride — GaN.

From EV chargers to drone systems and compact consumer electronics, GaN is enabling higher efficiency, dramatically smaller form factors and faster switching speeds than silicon can offer. So how do these two materials actually compare — and why is GaN being called the next semiconductor revolution?

Silicon in Power Electronics — The Established Standard

Silicon has been the dominant semiconductor material in power electronics for over 50 years. It is used in power supplies, battery chargers, inverters, motor drives and switch-mode power supplies (SMPS) globally.

Its widespread adoption comes down to three factors:

• Cost-effective, mature manufacturing processes with global supply chains
• Reliable, well-understood performance at moderate power levels
• Decades of design tooling, reference designs and engineering expertise

What is Gallium Nitride (GaN)?

Gallium Nitride is a wide bandgap semiconductor — a class of materials with superior electrical properties compared to silicon. Its wider bandgap means it can sustain much higher electric fields before breaking down, switch much faster and generate far less heat in the process.

Key electrical properties of GaN:

• Bandgap: 3.4 eV (vs silicon's 1.1 eV) — allows higher voltage operation
• Electron mobility: significantly higher — faster switching with lower resistance
• Breakdown voltage: much higher — safe at voltages where silicon fails
• Switching losses: dramatically lower — more efficient high-frequency operation

GaN vs Silicon — Parameter by Parameter

Parameter	Silicon	GaN
Efficiency	Moderate (~88–92%)	Very High (>95%)
Switching Speed	Limited (kHz range)	Extremely High (MHz range)
Size & Weight	Larger passive components	50–60% more compact
Heat Generation	Higher losses → more heat	Lower losses → less heat
Breakdown Voltage	~650V typical limit	650V+ with lower resistance
Power Density	Moderate	High
Maturity	Fully mature	Rapidly maturing
Cost	Lower	Higher (but falling fast)

Why GaN Changes Everything

1. Higher Efficiency — Less Energy Wasted

GaN-based power conversion systems consistently achieve efficiencies above >95% — versus silicon's typical peak of 88–92%. In a charging system operating continuously, this difference is substantial. Less energy wasted as heat means faster effective charging, lower electricity consumption and lower operating costs over the product's lifetime.

2. Dramatically Smaller and Lighter Chargers

Because GaN switches at much higher frequencies (into the MHz range versus silicon's kHz), the passive components — transformers, inductors and capacitors — can be made significantly smaller. The result is a charger that delivers the same power output in 50–60% less volume than an equivalent silicon design.

For drone systems where every gram matters, and for onboard EV chargers where space is at a premium, this is transformative.

3. Lower Thermal Footprint

Lower switching losses mean less heat generated inside the power supply. This has a cascading effect on the system design: smaller or fewer heatsinks, reduced or eliminated cooling fans, and a smaller, lighter, more reliable enclosure overall. In sealed or harsh environments — medical equipment, outdoor industrial systems, drone payloads — thermal management is often the hardest engineering constraint to solve. GaN significantly relaxes it.

4. Faster Switching — Better Control

GaN transistors switch at speeds that are impossible for silicon to match. This enables more sophisticated, high-precision charging algorithms — better regulation, tighter voltage control and faster response to changing battery conditions. For applications like medical devices and precision test equipment, this level of control is essential.

5. Ideal for High-Frequency Applications

GaN is especially well-suited to designs that operate at high frequencies — resonant converters, wireless power systems and advanced power factor correction stages. Higher operating frequency means better filtering, better dynamic response and less audible noise from the power supply.

When to Use Silicon — and When to Use GaN

Why GaN Matters for EV Chargers and Drone Systems

EV charging and drone operations share a common set of demands: high efficiency to minimise energy waste, compact size to reduce weight or footprint, and reliable thermal performance to sustain operation in demanding environments.

• EV onboard chargers: GaN enables compact, lightweight onboard chargers that fit within constrained vehicle packaging while achieving higher charge rates
• Fast-charge stations: Higher efficiency reduces heat at the station, allowing denser installations and lower cooling infrastructure costs
• Drone battery systems: Lighter chargers with faster high-current charging cycles extend effective operational time for UAV fleets

Challenges of GaN — Where Engineering Expertise Matters

GaN is not a drop-in replacement for silicon. It introduces real engineering challenges:

• Layout sensitivity: GaN devices switch so fast that parasitic inductance in PCB traces becomes a significant issue — board layout requires expert attention
• Gate drive design: GaN transistors require tightly controlled gate drive signals; getting this wrong causes oscillation or device failure
• EMI management: High switching speeds generate higher-frequency electromagnetic interference that must be carefully filtered
• Design complexity: Control algorithms and protection systems must be designed for GaN's faster dynamics

The Future: GaN is Just Getting Started

GaN manufacturing is scaling rapidly. Costs are falling year on year as fabrication processes mature and wafer sizes increase. Where GaN was once reserved for premium or specialised applications, it is increasingly viable for mainstream power electronics.

Industry analysts expect GaN to become the default choice for power supplies above a certain efficiency threshold within the next five to seven years — displacing silicon the same way silicon displaced earlier technologies before it.

Ergen's Approach: The OptiGaN Platform

Our in-house PCB design, firmware and test capability means we are not relying on reference designs — we are building GaN charging systems from first principles, with full control over every layer of the stack.

OptiGaN will be available across a power range designed to serve drone charging, EV applications, medical systems and industrial power conversion.

Conclusion

The transition from silicon to GaN is not an incremental upgrade — it is a fundamental shift in what power electronics can achieve. GaN delivers higher efficiency, smaller size, lower heat and better performance across every metric that matters for modern charging systems.

As industries from mobility to medical to defence demand more from their power systems, GaN is the technology that makes it possible. The question for engineers and product teams is no longer whether to move to GaN — it is when, and with whom.