TVS diode for 300 V rails — what the ratings mean on the bench
The 1.5KE350A-B: The 300 V reverse standoff voltage means this part sits across a 300 V DC rail and stays transparent until a transient pushes the line above 332 V, where breakdown begins.
Package and board-fit reality
The bulk packaging means these ship loose in a bag or tube, not on tape-and-reel — plan for hand-insertion or tube-fed wave solder. No power line protection rating — this is a signal- or DC-rail clamp, not a mains-side MOV replacement.
Obsolete — sourcing the 1.5KE350A-B today
Diodes Incorporated lists the 1.5KE350A-B as Obsolete. For an existing BOM line that calls out this exact part, independent distribution channels carry remaining inventory.