SLUS794F November 2007 – April 2016 UCC28070
Interleaved PFC techniques dramatically reduce input and output ripple current caused by the PFC boost inductor, which allows the circuit to use smaller and less expensive filters. To maximize the benefits of interleaving, the output filter capacitor should be located after the two phases allowing the current of each phase to be combined together before entering the boost capacitor. Similar to other power management devices, when laying out the PCB it is important to use star grounding techniques and to keep filter and high frequency bypass capacitors as close to device pins and ground as possible. To minimize the possibility of interference caused by magnetic coupling from the boost inductor, the device should be located at least 1 inch away from the boost inductor. TI recommends the device not be placed underneath magnetic elements.