The design combines high efficiency, precise control, and compactness, making it an excellent choice for high-power applications in demanding environments and the flexible control options and stable performance add to its appeal for enterprise-level power management solutions.
The High Voltage 800-W SEPIC (Single-Ended Primary-Inductor Converter) Converter Reference Design offers an efficient solution for powering server battery backup systems. This design is particularly important in critical applications where uninterrupted power is essential, such as in data centers, telecommunications, and industrial servers. By providing a reliable and high-efficiency power conversion method, this SEPIC converter enables seamless battery charging and management, which is essential for ensuring that servers and other critical infrastructure maintain operation during power outages or fluctuations. The SEPIC topology used in this reference design is well-suited for applications that require a wide input voltage range, ensuring adaptability to varying power sources. Furthermore, this design incorporates features that protect against over-voltage and over-current conditions, thus enhancing system stability and longevity, making it a valuable reference for engineers working on high-reliability power solutions.
This PMP22339 reference design by Texas Instruments operates in discontinuous conduction mode (DCM) and features a non-isolated topology, offering versatile output voltage and current adjustments. Users can set the output voltage between 282 V and 400 V by adjusting an external DC voltage within the 0 V to 3 V range. Similarly, the output charging current is adjustable from 0 A to 2 A through duty cycle adjustments on a PWM input. This design supports an input voltage range of 340 Vdc to 420 Vdc, providing flexibility to adapt to various power input requirements. To maintain precise regulation, independent feedback loops for both voltage and current are used, ensuring stable and accurate performance.
This SEPIC converter demonstrates a high efficiency of 97% at full power (380 V input, 400 V output at 2 A), making it well-suited for energy-efficient applications. The design achieves an accuracy of 1% for voltage regulation and 2% for current regulation, which is crucial for applications requiring precise power delivery. For ease of integration, the design can interface seamlessly with digital-to-analog converters (DACs) or microprocessors, and it also offers the option for manual control, enhancing its adaptability across different systems. The use of silicon carbide (SiC) FETs and rectifiers in the design helps minimize both switching losses and ringing, contributing to the converter’s high efficiency and reliable operation. This efficiency, combined with a compact PCB footprint of 116 mm x 95 mm, makes it ideal for use in space-constrained environments.
The design is identified by the part number PMP22339.1 and has the following specifications: a minimum input voltage of 340 V, maximum input voltage of 420 V, nominal output voltage of 400 V, maximum output current of 2 A, and maximum output power of 800 W. The non-isolated topology facilitates a simpler design with efficient energy transfer, which is advantageous in applications that do not require isolation but benefit from space-saving designs and straightforward configurations. As a result, this SEPIC converter is well-suited for use in enterprise systems and rack server motherboards, where compact, reliable, and efficient power solutions are essential.
TI 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.
