What the clamping specs mean for your protection circuit
The 1.5SMCJ130CA: The reverse standoff of 130 V defines the working voltage the TVS sees in normal operation — it idles below breakdown and draws only leakage current until a surge arrives. At 144 V minimum breakdown, the device transitions into conduction; the clamping voltage of 209 V at 7.2 A peak pulse (10/1000 µs waveform) is the ceiling the downstream load never exceeds. That 65 V gap between standoff and clamping is the let-through headroom — a sensitive 130 V rail with tight overvoltage tolerance needs a closer standoff-to-clamp ratio than this part delivers, so check the downstream IC's abs-max rating against 209 V before committing it to a 130 V data or power line. A sub-microsecond ring or ESD zap delivers its energy in a shorter time constant; the TVS will clamp it but the let-through voltage profile differs from the datasheet test condition, so look at the Vc waveform shape in the Diotec curves if the threat includes fast transients.
Thermal and package — the 150°C junction ceiling
In a repetitive-surge environment (cyclone cabinet, AC-line close to the TVS), budget the thermal rise per Diotec's RthJA curves and confirm the PCB copper area under the tab is sufficient. Operating from -50°C to 150°C junction covers the industrial cold-start case and the elevated-ambient hot side, so the part is viable in outdoor enclosures and factory-floor panels that see wide temperature swings. The strip packaging is reel-free loose stock — for high-volume production verify that the tape-and-reel option exists in the Diotec series before planning a fully automated line load.
Listed as Active under Diotec Semiconductor. This part carries no power-line-protection certification — the absence of a UL 1449 listing means it cannot be marketed as a per-point-of-entry TVS on an AC line. It is correctly positioned as a board-level transient suppressor for DC rails or signal lines, not as a front-door AC service entrance device.