Transient protection in a DO-214AA footprint
It is rated for a peak pulse power of 600W and a peak pulse current of 68A under the 8/20 µs waveform, with a reverse standoff voltage of 28.2V and a minimum breakdown voltage of 31.4V. The single bidirectional channel protects against surges of either polarity, making it a straightforward choice for unipolar or bipolar rail clamping in a single SMB (DO-214AA) package.
Above that, the device begins to break down at a guaranteed minimum of 31.4V. For a 24V nominal rail (common in industrial control and telecom), the 28.2V standoff provides enough margin to avoid nuisance triggering from normal ripple, while the 59V clamp keeps the protected node within the safe operating area of most downstream 60V-rated components.
The base product number is SM6T33, so the 'CA' suffix confirms the bidirectional polarity variant.