Standoff, breakdown, and clamping — the voltage triad
The 1N6271A-E3/73: The reverse standoff of 8.55V (typ) is the working voltage the TVS sees in normal operation — the diode sits off-state below the breakdown knee. Once the surge pushes the cathode above the 9.5V minimum breakdown, the device avalanches and clamps at 14.5V maximum. That clamping-to-standoff ratio matters: for an 8.55V working rail, a 14.5V let-through is acceptable for most logic and semiconductor inputs, but sensitive analog front-ends with sub-12V rails need to confirm the 14.5V ceiling clears their abs-max rating with margin. The TransZorb® series is the Vishay brand name for their Zener-based TVS — it follows the same avalanche-mechanism as a Zener but is characterised and rated for pulse-surge environments, not continuous DC regulation.