100 W LLC DC-DC Converter Reference Design

The converter design gives effectivity and compact design, appropriate for industrial gear and varied functions, reaching 88% effectivity at full load.

The LLC DC-DC Converter is a extremely environment friendly and versatile energy conversion answer extensively utilized in functions that require compact measurement, minimal warmth era, and secure efficiency. It operates with excessive effectivity by using an LLC resonant circuit, which permits Zero Voltage Switching (ZVS) and considerably reduces switching losses, particularly at excessive frequencies. This effectivity is essential in functions like information facilities, industrial gear, and automotive techniques, the place vitality financial savings, energy density, and thermal administration are priorities. By offering secure output with minimal noise and electromagnetic interference (EMI), LLC DC-DC converters play a significant function in trendy energy electronics, supporting developments in efficiency and sustainability. A 100 W LLC DC-DC Converter reference design from Toshiba is appropriate to be used in industrial gear related to 24 V output AC-DC converters, in addition to in varied different functions.

The ability provide generates a 12 V output utilizing an LLC resonant circuit. The LLC circuit alternates the high-side and low-side MOSFETs on the first (enter) facet at a 50% responsibility cycle, adjusting the switching frequency in line with the load to manage the output voltage. A useless time is launched throughout the switching of MOSFETs to stop the shoot-through phenomenon. Throughout this era, ZVS happens as a consequence of resonance, minimizing switching losses and contributing to excessive effectivity.

This energy provide affords a complete effectivity of 88% at full load and incorporates a compact define measurement of 110 mm x 110 mm x 35 mm, excluding enter and output terminals on the bottom. It makes use of optimized energy MOSFETs and a photocoupler to reinforce efficiency and reliability. On this energy provide, the enter voltage is stepped all the way down to 12V by the LM46000 converter, which then provides this 12V to the LLC controller to start out the ability provide’s operation. The enter voltage vary is set by the resistance values of exterior resistors, which set the minimal working voltage limits. 

These limits are established by dividing the enter voltage by resistors and feeding the divided voltage to the allow pin of the DC-DC converter. The converter begins switching when the allow pin voltage exceeds the edge of two.0V. 

The design of the gate drive circuit considerably influences each energy provide effectivity and EMI. Sometimes, there’s a trade-off between reaching excessive effectivity and minimizing EMI, so a balanced design is crucial. Whereas the LLC circuit advantages from low EMI as a consequence of Zero Voltage Switching (ZVS) operation, switching noise can nonetheless contribute to EMI points. The output voltage of the ability provide is about by exterior resistors and a shunt regulator. The shunt regulator adjusts the present by the photocoupler to make sure that the voltage obtained by dividing output voltage with exterior resistors matches the reference voltage.

Toshiba has examined this reference design. It comes with a invoice of supplies (BOM), schematics, meeting drawing, printed circuit board (PCB) format, and extra. The corporate’s web site has extra information in regards to the reference design. To learn extra about this reference design, click on right here.