What the ratings mean for a 300V rail
The 1.5KE350CAHA0G: Its 300V reverse standoff voltage means it sits across a 300V nominal DC bus without conducting until a transient pushes the line past 333V (the minimum breakdown voltage). When the transient hits, the diode clamps at 482V maximum, shunting up to 3.2A of peak pulse current away from the downstream circuitry. That clamp voltage is the ceiling the protected device sees — a 300V-rated MOSFET with a 500V drain-source breakdown has margin here.
The DO-201AA (DO-27) axial package is through-hole — the leads absorb thermal shock during soldering and the body can be reworked with standard hot-air or iron methods. No moisture sensitivity level to track; it ships in Tape & Box.
Active production — sourcing posture
For a 300V bidirectional TVS in a DO-201 footprint, this is the direct order code.