Clamping a 6.5V rail — what the ratings mean
The SMBJ6.5CA-13-F: Its 6.5V reverse standoff voltage means it sits across a 5V or 6V supply rail without conducting in normal operation — it only starts clamping when the transient exceeds the 7.22V minimum breakdown voltage. At the full 53.6A peak pulse current, the clamping voltage holds at 11.2V max.
Field swap and package note
DO-214AA (SMB) surface-mount package — the body is large enough to hand-solder with a fine tip iron if you are replacing it on a board without a hot-air station. Polarity is not an issue here: bidirectional means both directions clamp identically, so orientation does not matter. That saves a board spin if the footprint was laid out for a unidirectional part.
Sourcing and compliance
No power line protection rating (the spec says 'Power Line Protection: No') — this is a signal-line or low-voltage rail TVS, not a mains-side suppressor. Use it on data lines, I/O ports, or DC supply rails up to 6.5V.