intent/protection-ovp

Remedy ¶

Fit the over-voltage clamp the intent declares for this rail, chosen to conduct below the lowest absolute maximum the rail feeds.

What it means ¶

The design intent declares that a named rail must be over-voltage protected. This rule probes that exact net for a TVS or a zener among its components. It fails when the declared rail carries no such clamp. It keys on the declared net NAME, not on the rail-role heuristic. That heuristic misses names like VBATT01 that carry no voltage token. Keying on the name makes an input rail checkable once the declaration names it explicitly.

Why engineers want it ¶

An input that can see a transient (a battery rail, an off-board connector) is supposed to have a clamp that shunts the spike to ground before it reaches downstream silicon. The netlist does not state whether a given rail was intended to be protected. That is an architecture decision, so the intent declaration names the rail and this rule verifies the clamp is actually on it.

Impact ¶

The design was intended to protect a rail, and that rail has no OV clamp. So a transient reaches downstream parts and causes latch-up, degraded silicon, or an immediate failure on a hot-plug or load-dump event.

Scope note ¶

ovp is realized by a TVS or a zener on the rail (component.class tvs/zener). It is one of the per-kind protection rules (intent/protection-ovp, intent/protection-discharge), each emitted only when the declaration carries that kind, so distinct review items bind independently. The rule iterates the declared protections and probes the design; it never derives the protected-rail set from the netlist.