Transient suppression for 16V rails
The SMCJ16A-13 is a 1500W Zener TVS diode from Diodes Incorporated, designed to clamp transients on 16V nominal rails. This means a downstream IC rated for, say, 30V absolute maximum sees a clamped surge well within its margin — the TVS absorbs the energy, not the protected device.
Package and board fit
Housed in a DO-214AB (SMC) package, this is a surface-mount device with a standard footprint shared across the SMCJ family. It is a unidirectional device — one channel per package. The cathode band on the package body marks the protected line side; the anode connects to ground. For bidirectional protection on AC or bipolar rails, two devices or a bidirectional variant is needed.