Surge rating and protection window — what 1500 W means on the rail
The 1.5SMBJ18A-H: The 18 V reverse standoff voltage means the diode is effectively invisible to the circuit under normal operation — it only starts conducting when the line voltage exceeds 20 V (minimum breakdown), which is above the 18 V rail tolerance. Unidirectional configuration (single channel) clamps positive transients to ground; for AC lines or bidirectional protection, a different part from the same series is needed.
Package and temperature envelope for board integration
Tape & Reel packaging is the standard SMD format for pick-and-place; the reel quantity is the procurement unit for volume BOM lines.