Where the ratings matter for BOM fit
The 1.5SMC200CA-M3/57T: The 171 V reverse standoff voltage means the diode does not conduct at normal operating levels below that rail — it sits transparently across the line until a transient pushes the voltage past the 190 V breakdown threshold. The 274 V clamping voltage is the maximum the protected circuit sees during the surge event; downstream components must be rated to survive this peak without damage. The 5.5 A peak pulse current at the 10/1000 µs waveform defines the survivable surge energy: a higher-energy transient (longer pulse or higher current) would exceed the diode's thermal capacity. Operating temperature spans -65°C to 150°C junction, covering industrial enclosures and under-hood automotive environments without derating concerns at the high end. The bidirectional configuration means a single device protects both polarities, simplifying board layout for AC lines or DC rails subject to reverse surges.