This reference design is a compact, high efficiency, 24-V DC, 500-W reference design for industrial AC/DC power supplies. This design consists of a front-end, two-phase interleaved transition mode (TM) power factor correction (PFC) based on the UCC28064A. This minimizes the PFC inductor size and reduces EMI filter requirements. The DC-DC is implemented using the HB-LLC stage implemented using TI's UCC256301 device. For efficiency improvement, synchronous rectification is used at secondary which uses the UCC24612.
Features
- Overall efficiency of 94.5% at full load with peak efficiency > 95%
- Up to 330-W operation without forced cooling
- High power factor > 0.99 and meets PFC regulations and current THD as per IEC 61000-3- 2 Class A
- Meets requirements of conducted emissions standard (EN55011 Class B)
- ZCS avoidance feature and OVP sensing feature in LLC controller improves robustness and protects systems from overcurrent, short circuit, and overvoltage to ensure safety
- Small 160 mm × 80 mm × 35 mm PCB form factor