Flyback ICs Extend Power Range to 440 W

Power Integrations has introduced a new generation of flyback switching ICs that extend the usable power range of flyback converters to 440 W. The TOPSwitchGaN family combines gallium nitride (GaN) technology with established control architecture to simplify power supply design.

Context: Limitations of traditional flyback designs
Flyback converters are widely used in low- to mid-power applications due to their simplicity and cost efficiency. However, at higher power levels, designers have typically transitioned to more complex resonant topologies such as LLC to maintain efficiency and thermal performance.

Power Integrations addresses this limitation by extending the flyback topology into higher power ranges, reducing the need for more complex circuit designs.

Technology: Integration of GaN and control architecture
The TOPSwitchGaN IC family integrates 800 V PowiGaN switches with the company’s established TOPSwitch control architecture. GaN devices offer lower on-resistance compared to silicon, reducing conduction losses and enabling higher efficiency.

The ICs operate at switching frequencies of up to 150 kHz, allowing smaller transformer designs and contributing to more compact power supplies. Across load conditions from 10% to 100%, the system achieves efficiency levels of up to 92%.

Standby power consumption remains below 50 mW, meeting European ErP requirements without requiring synchronous rectification.

Design impact: Reduced complexity and system cost
By enabling higher power output within a flyback architecture, the ICs reduce the need for resonant or LLC designs, which typically require more components and design effort.

The solution can eliminate heat sinks in certain configurations and simplifies thermal management. Pin-to-pin compatibility with existing off-line switcher ICs allows designers to scale designs from 10 W to 440 W using similar design methodologies.

Packaging options and application range
Two packaging options are available to support different design requirements. A low-profile surface-mount package supports compact designs up to 135 W without additional heat sinking, while a vertically oriented package enables higher power operation with optional heat sink attachment.

These configurations support applications such as household appliances, industrial power supplies, power tools, e-bikes, and garage systems.

Performance characteristics and operational benefits
The ICs deliver low switching and conduction losses, high surge tolerance, and efficient standby operation. In standby mode, the system can supply auxiliary power for housekeeping functions while maintaining low input consumption.

Reference designs demonstrate application-specific implementations, including appliance power supplies, industrial systems, and battery charging solutions.

Conclusion: Expanding flyback applicability in power design
With the introduction of TOPSwitchGaN, Power Integrations extends the practical limits of flyback converters into higher power ranges traditionally reserved for more complex topologies. This approach enables simpler, more cost-effective power supply designs while maintaining efficiency and compliance with energy standards.

Edited by an industrial journalist, Lekshman Ramdas, with AI assistance.

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