Transient protection for 110V rails – what the ratings mean
The 122V minimum breakdown voltage gives a 12V margin above the working rail before clamping starts — enough headroom for a 110V DC bus or AC line after rectification without nuisance triggering. That clamp voltage is the ceiling the protected circuit sees; a downstream DC-DC converter or relay coil rated for 200V would survive this transient.
Package and thermal routing in the DO-214AC (SMA) footprint
Housed in the DO-214AC (SMA) surface-mount package, this part reflows on a standard 2-layer board. The cathode tab on the SMA footprint is the primary heat path — the copper pad area under it directly sets the junction-to-ambient thermal resistance. For a 500W pulse, the thermal mass of the pad and board absorbs the energy; a 1 oz copper pour of at least 300 mm² is typical to keep the junction within the -65°C to 150°C operating range.