Dual 40 A fast recovery diode in an ISOTOP baseplate package
The STTH60L06TV2 from STMicroelectronics is a dual-diode module in the ISOTOP package, containing two independent 600 V, 40 A fast recovery diodes with a 90 ns reverse recovery time. The ISOTOP package is designed for chassis mounting with a large copper baseplate that bolts directly to a heatsink, making the thermal path from junction to ambient short enough to sustain 40 A per diode in continuous operation. This part is a standard-technology fast recovery diode, not a Schottky or SiC device — the 1.55 V forward voltage drop at 60 A is typical for a 600 V epitaxial structure, and the 90 ns trr keeps switching losses manageable in hard-switched PFC and output rectifier stages operating above 20 kHz.
The 90 ns reverse recovery time places this diode in the fast-recovery class, defined as trr ≤ 500 ns at rated current. In a continuous-current-mode (CCM) boost PFC stage at 50 kHz, the 90 ns trr limits the reverse-recovery charge that the MOSFET must absorb during turn-on, keeping the switching node voltage overshoot within the 600 V rating. Maximum junction temperature is 150 °C, and the 25 µA reverse leakage at 600 V is specified at room temperature — expect leakage to multiply by roughly 10× at 125 °C junction, which is normal for a 600 V epitaxial diode and must be factored into the thermal budget.
No official replacement part number is recorded in the STTH60 family for this specific ISOTOP dual-diode variant.