Dual 10 A rectifier in a single TO-220
The NXP BYT28-300,127 packs two 300 V, 10 A ultrafast rectifiers with a common cathode into a single TO-220AB package — one device handles the full-wave centre-tap or half-bridge leg that would otherwise need two separate diodes. Each diode is rated for a 60 ns reverse recovery time, placing it in the fast-recovery class (≤ 500 ns, > 200 mA). That 60 ns trr keeps switching losses low in a 50-100 kHz PFC boost stage or output rectifier.
What the ratings mean for your BOM
The 300 V Vrrm gives headroom for a 240 VAC input with a 1.4× derating factor — the diode sees about 340 V peak after the bridge, so 300 V per junction is tight unless you split the voltage across the two diodes in series. For a 120 VAC input (170 V peak) it is comfortable. At 10 A average forward current per diode, the forward drop is 1.4 V max — that is 14 W conduction loss per junction at full load. Reverse leakage is 10 µA at the rated 300 V — negligible at room temperature, but it doubles every 10 °C junction rise. At 125 °C expect roughly 160 µA, still acceptable for most offline supplies.
Active production — sourcing posture
It is a standard catalogue part in the TO-220AB package, sourced through authorized distribution.