30 ns trr — where this diode fits the switching loop
The 1N6620US/TR is a fast recovery diode rated for 1.2 A average rectified current and 220 V reverse voltage, with a reverse recovery time of 30 ns. That trr puts it squarely in the 100 kHz+ switching range — a PFC boost stage, a flyback snubber clamp, or a high-frequency output rectifier where a standard recovery diode would overheat from reverse recovery losses. The SQ-MELF (A-MELF) package is a hermetic glass body with metallized end caps — no plastic molding, no moisture ingress path.
Parametric floor — what the numbers mean for the BOM line
Forward voltage is 1.4 V max at the full 1.2 A rated current. At 1.2 A and 30 ns trr, the switching loss term (0.5 × Vf × If × trr × f) dominates at frequencies above 200 kHz — the diode's thermal limit in the SQ-MELF body is set by the sum of conduction and switching losses, not by the average current alone. Reverse leakage is 500 nA max at 220 V and 25°C, doubling roughly every 10°C. At 125°C junction the leakage is in the low microamp range — negligible for the rectifier's efficiency but relevant if the diode sits across a high-impedance node where leakage could pull a bias rail out of regulation. Junction capacitance is 10 pF at 10 V reverse bias. This is low enough that the capacitive switching loss (0.5 × Cj × Vr² × f) stays under 10 mW at 500 kHz, so the trr is the dominant switching parameter, not the junction charge.
Active lifecycle — no LTB clock ticking
The Tape & Reel packaging (TR suffix) is the standard surface-mount reel format. Volume quotes are confirmed against the BOM quantity at RFQ time; the part is sourced through authorized distribution with full traceability.