60 V / 20 A FERD — conduction loss and recovery profile
The FERD20U60DJFD-TR is a 60 V, 20 A Field Effect Rectifier Diode from STMicroelectronics, built on the FERD (Field Effect Rectifier Diode) technology that delivers a forward voltage of 510 mV at the full 20 A rated current. This low Vf directly reduces conduction losses in the rectification stage, which matters for thermal budget in a compact PowerFlat 5x6 package. The fast recovery classification (<500 ns, >200 mA Io) means this diode is not limited to line-frequency rectification — it can handle the switching transitions in a continuous-conduction-mode PFC boost stage or a secondary-side synchronous rectifier replacement in an isolated DC-DC converter.
PowerFlat 5x6 — thermal and footprint constraints
The thermal resistance to the board depends on the pad area and the number of thermal vias under the die attach pad — a 1-inch-square copper pour with 9 vias is a typical starting point for a 20 A continuous application. The junction temperature ceiling is 150 °C. At 20 A with a 510 mV drop, the conduction loss is 10.2 W; the PCB copper area and airflow must keep the junction below this limit at the ambient operating temperature.