500 W bidirectional TVS in a hermetic MELF package
The 1N6133AUS is a bidirectional Zener TVS diode from Microchip Technology rated for 500 W peak pulse power per the 10/1000 µs waveform. It clamps transients on a 98.8 V nominal rail, with a minimum breakdown of 123.5 V and a maximum clamp of 178.8 V at 2.8 A peak pulse current. Bidirectional operation means a single device protects against both positive and negative surges, which halves the component count versus a pair of unidirectional diodes on a bipolar line.
Clamping voltage and peak current — what they mean for protection margin
With a 98.8 V standoff, the diode does not conduct at the normal rail voltage. The 123.5 V minimum breakdown ensures it starts clamping before the downstream silicon sees damage. The 178.8 V maximum clamp at 2.8 A is the ceiling the surge sees — the protected circuit must survive that peak for the 10/1000 µs pulse duration. The 500 W peak pulse rating is the product of clamp voltage and peak current at the test waveform. If the real-world transient is shorter (e.g. 8/20 µs), the diode can absorb a higher peak current — but the datasheet 10/1000 µs rating is the baseline for comparing parts across the 500 W TVS class.
Active production — sourcing posture for the BOM
No end-of-life notice or successor has been published. The SQ-MELF B package is a non-standard cylindrical footprint — confirm your pick-and-place feeder and stencil aperture before committing the assembly.