Featuring PFC and flyback topology, 90% efficiency, and built-in EMI and surge protection, the compact solution offers robust thermal performance and design flexibility with comprehensive documentation and PCB layout support.
Design engineers working on LED lighting systems for commercial and industrial environments often face higher power requirements than residential setups. Commercial lighting systems demand not only robust power delivery but also reliable thermal management due to extended operating hours and elevated ambient temperatures. This reference design by Toshiba outlines a compact, high-efficiency 100W power supply intended for such applications. It offers engineers a practical blueprint that balances electrical performance, thermal dissipation, and EMI compliance—key considerations in professional lighting infrastructure.
Unlike residential lighting, where power supplies are often miniaturized and embedded within the lamp enclosure, commercial systems typically allow for standalone power supply units. This eases space constraints and enables the use of heat sinks for thermal management. To streamline heat dissipation, this design uses a through-hole insulated package that permits direct heat sink mounting without needing additional insulating sheets, simplifying assembly and improving reliability.
The power supply comprises two major stages: a Power Factor Correction (PFC) circuit followed by a flyback converter. The PFC boosts the input AC voltage to a stable DC level of approximately 390 V. The subsequent flyback stage regulates this down to a constant output of DC 110 V at 1.04 A, ensuring the lighting system receives a stable, flicker-free current source. The choice of MOSFETs in both the PFC and flyback circuits is based on efficiency and thermal performance under high-voltage operation.
To enhance system protection and EMI performance, several supporting components are integrated. A ceramic varistor (RV1) protects against surge voltages, such as those caused by nearby lightning strikes. X capacitors (Cx, C4, C8) and a common mode choke (L2) help suppress both common-mode and differential-mode noise, ensuring electromagnetic compatibility. Discharge resistors (R146–R149) are employed across capacitors to meet safety discharge standards. Designers are encouraged to adjust these components based on the PCB layout and enclosure to optimize EMI suppression.
Rectification is handled by a bridge diode (D4), selected to tolerate the expected inrush currents and peak voltages in the operating range. With a high conversion efficiency of 90% at 230 V input and full load, the design supports energy savings and reduced thermal buildup. The power supply’s compact form factor—measuring just 180 mm × 57 mm × 40 mm—makes it suitable for a wide range of commercial lighting applications.
This reference design provides a complete solution for engineers, including guidance on power device selection (MOSFETs and photocouplers), noise suppression strategies, and heat dissipation methods—enabling quicker development cycles and enhanced reliability in high-power LED lighting systems.
Toshiba has tested this reference design. It comes with a bill of materials (BOM), schematics, assembly drawing, printed circuit board (PCB) layout, and more. The company’s website has additional data about the reference design. To read more about this reference design, click here.
