30 A, 600 V, 50 ns — the fast-recovery diode for automotive power stages
The STTH30ST06GY-TR is an STMicroelectronics automotive-grade fast-recovery diode rated for 30 A average rectified current and 600 V reverse voltage, with a 50 ns reverse recovery time. It comes in a D2PAK (TO-263-3) surface-mount package and carries AEC-Q101 qualification, confirming it was released for automotive power-train, on-board charger, and DC-DC converter applications where switching losses dominate the thermal budget.
Why the 50 ns trr matters for the switching loss budget
A 50 ns reverse recovery time at 30 A forward current places this diode in the fast-recovery class — the recovery charge is low enough that a continuous-conduction-mode boost or PFC stage running at 50–100 kHz does not burn excessive switching loss in the diode itself. The 3.6 V forward drop at 30 A is the conduction-loss floor; at high junction temperature the forward voltage rises and the thermal margin narrows.
STMicroelectronics lists the STTH30ST06GY-TR as Obsolete. The AEC-Q101 automotive qualification means any replacement must match the same qualification level if the end equipment requires it.
D2PAK footprint — what a replacement must match
The D2PAK (TO-263-3) package has a large tab that carries the cathode connection and conducts heat to the PCB copper plane. The pinout is standard: anode, cathode (tab), and a third pin that is also cathode on most parts in this family. Any pin-compatible replacement must share the same tab-connected cathode and the same 2.54 mm pin pitch to drop onto the existing PCB footprint without a layout change.