Transient protection for 24V rails – 1500W peak pulse power
The 1N6281A is a Zener TVS diode from the onsemi Mosorb™ series, rated for 1500W peak pulse power. That 1500W rating is the energy-handling ceiling for an 8/20 µs surge waveform – enough to clamp transients on a 24V DC bus without exceeding the 37.5V clamping voltage. It protects a single unidirectional line, with a reverse standoff voltage of 23.1V and a minimum breakdown of 25.7V. The 23.1V standoff sits comfortably below a 24V nominal rail, so the diode stays off during normal operation and only conducts when a surge pushes the line above the breakdown threshold.
onsemi lists the 1N6281A as Obsolete. The operating temperature range of -65°C to 175°C is wide enough for military, avionics, or downhole applications – but the obsolete status means any design still using this part should have a qualification plan for an alternative before the available inventory dries up. No power line protection feature – this is a standard Zener TVS, not a crowbar or a filtered suppressor. The application is general-purpose transient clamping on signal or low-power DC lines.
Package and mounting – DO-201AD axial checklist
The DO-201AD axial package is a through-hole, leaded form factor. The body diameter and lead spacing are standard for this JEDEC outline – the hole diameter on the PCB should match the lead diameter from the datasheet drawing to avoid solder-joint cracking under thermal cycling. Hand-solder or wave-solder only.