Zero trr — the switching-loss argument for SiC
The IDL04G65C5XUMA2 is an Infineon CoolSiC™+ silicon-carbide Schottky diode rated at 650 V reverse voltage and 4 A average rectified current. Its defining spec is a zero reverse recovery time — the device stores no minority charge, so there is no reverse-recovery current spike when the diode commutates. That eliminates the turn-on loss in the companion MOSFET and shrinks the snubber network to a bare minimum.
175 °C junction — thermal headroom in a tight PFC loop
That 175°C ceiling matters in a continuous-conduction PFC boost stage where the diode carries the full DC bus current and sits next to hot magnetics. The forward voltage drop is 1.7 V max at 4 A and 25°C — at elevated junction temperature Vf climbs, but the wide Tj margin keeps the part inside the SOA without derating the load.
PG-VSON-4 footprint — thermal pad is non-negotiable
The diode comes in a 4-PowerTSFN package, also designated PG-VSON-4. This is a small, 4-pin DFN with an exposed bottom-side pad. Without that copper spreading plane the junction-to-board thermal resistance rises and the 175°C rating becomes academic.