33 V rail clamp in a DO-214AC footprint
The reverse standoff voltage is 33 V (typ), meaning the diode does not conduct at normal rail voltage. Breakdown occurs at a minimum of 36.7 V, and the clamping voltage at peak pulse current (8.5 A) is 59 V max — that window between breakdown and clamp is the energy absorption zone. For a 33 V supply, this margin ensures the TVS does not trigger on ripple but still catches transients before they reach downstream silicon.
Microchip lists the SMAJ33E3/TR13 as Active. For volume BOM positions, this part can be quoted to order against your quantity — no supply-chain discontinuity to plan around.
The Zener type and unidirectional channel make it suitable for DC rail protection in power supplies, motor drives, and general-purpose circuit boards where a single polarity clamp is needed.