Obsolete — last-time-buy sourcing
The 1.5KE6.8C is marked Obsolete by Littelfuse, meaning the manufacturer has discontinued production with no scheduled last-time-buy window. For existing BOM lines, the only supply channel is independent distribution — surplus or new-old-stock lots, confirmed at RFQ.
1500 W pulse clamp — the real-world margin
That 1500 W rating is the non-repetitive ceiling — for repetitive surges, derate per the pulse derating curve in the datasheet. The 5.8 V reverse standoff voltage means the diode stays fully non-conductive below that DC rail, so it protects a 5 V supply bus without leakage until the transient exceeds the 6.12 V breakdown threshold.
A single bidirectional Zener die handles positive and negative transients symmetrically, eliminating the need for two back-to-back unidirectional diodes.
Sourcing reality for the BOM line
With no official successor from Littelfuse, the 1.5KE6.8C is a one-off order code. The 1.5KE series includes many voltage variants, but a drop-in replacement requires matching the 5.8 V standoff, 6.12 V breakdown, and 1500 W pulse rating.