The SMAJ11CA-13: The reverse standoff voltage is 11 V, meaning the protected rail can sit at 11 V DC without the diode conducting leakage. A single bidirectional channel handles positive and negative transients on the same line, which saves a diode and a PCB trace compared to back-to-back unidirectional parts.
Package, temperature, and board-fit
The SMA footprint is a standard JEDEC outline — the pad layout is well-documented and the part reflows cleanly with a typical lead-free profile. Power line protection is not claimed (the part lacks the low clamping factor needed for AC mains), but for DC power rails, signal lines, and I/O ports at 11 V or below, the 18.2 V clamp gives a solid guard band against 24 V transients or inductive kickback.
Active production — sourcing posture
The base product number is SMAJ11, and the -13 suffix denotes the Tape & Reel packaging option.