Clamping voltage and breakdown margin
The 1.5SMC120AHE3_A/H: Breakdown voltage starts at 114 V min, giving a 12 V window above the 102 V standoff before the device begins to conduct. The 165 V clamp at 9.1 A peak pulse current (10/1000 µs) defines the maximum voltage a downstream IC sees during a surge — a 24 V ECU with a 60 V abs-max rail has ample headroom. Operating temperature spans -65°C to 150°C junction, covering cold-crank and engine-bay heat soak conditions where the ambient can exceed 125°C.