The TIDA-01494 reference design is a compact, high efficiency, 24-V DC, 480-W nominal, 720-W peak output reference design for industrial AC/DC power supplies. The circuit consists of a front-end continuous conduction mode (CCM) power factor correction (PFC) circuit followed by a robust LLC stage with synchronous rectification. The design enables efficiency greater than 93.5% over a wide load range, allowing the system to work without forced cooling. The LLC stage, based on the UCC256301, takes advantage of the ZCS avoidance feature in the UC256301 to enable peak output power, minimizing the PFC Bulk capacitor for meeting holdup requirements, while making the system robust to short circuit and over current conditions. The UCC24612-2 based synchronous rectifier helps in minimizing the losses in the output rectifier, while its advanced proportional gate drive and dead time optimization features helps to avoid shoot through and minimizes losses.
Features
- Peak power conversion efficiency of 94% at 230V AC with average efficiency >93.5%
- Delivers 20A continuous current and up to 30A peak current for 3 seconds
- Power factor >0.99 and meets PF and current THD as per IEC 61000-3-2 Class A and EN55022 Class B Conducted Emission standard
- ZCS avoidance in the LLC stage, enabling wider input voltage range operation and robustness
- Over current, short circuit, over voltage and over temperature protection
- Compact form-factor: 155mm x 125mm