25 ns trr — the snubber-skipping spec
That 25 ns trr is the reason you pick this part over a standard recovery diode — it lets you skip the snubber on many 100 kHz hard-switched converters and PFC stages, saving two resistors and a capacitor per diode position. The pair shares a common cathode in a single TO-247-3 package, so one mounting hole and one heatsink handle both diodes.
30 A, 1.45 Vf — the thermal budget
At 30 A forward current each diode drops 1.45 V maximum. That is 43.5 W per diode at full tilt — the TO-247 package can shed that with a decent heatsink and forced air, but do not try to run both diodes at 30 A continuous without a fan and a properly sized heatsink. For a 1 kW PFC boost stage running at 10 A average per diode, the conduction loss sits around 14.5 W per diode — comfortable in a TO-247 with a modest extruded heatsink.
300 V Vrrm — what it fits
The 300 V maximum DC reverse voltage covers single-phase 240 VAC rectifier outputs (peaks around 340 V) with about 12 % margin — adequate for most designs, but check your worst-case line transient. It is also a standard fit for the boost diode in a 240 VAC input PFC stage running at 380–400 VDC bus. The 20 µA reverse leakage at 300 V is typical for a fast recovery diode at 25 °C; expect it to climb with junction temperature, but it stays under control below 125 °C.
ST lists the STTH60W03CW as Active. No end-of-life notice, no last-time-buy deadline to track for the current production run. The base product number STTH60 covers a family of current and voltage variants in the same TO-247 footprint, so if a future design needs a different voltage rating the PCB layout stays the same.