What the 600W peak pulse rating means on the bench
The SMBJ13A-13-F: With a 13V reverse standoff voltage (working voltage) and a 14.4V minimum breakdown, it starts conducting just above the rail and clamps at 21.5V maximum — the scorch mark tells you if the surge exceeded that ceiling. The 27.9A peak pulse current rating at 10/1000µs is the current it can sink during that 1ms pulse; a longer or higher-energy transient will punch through the silicon.
Package and board-fit for the DO-214AA SMB
Housed in the DO-214AA (SMB) package, this is a surface-mount diode with a supplier device package designation of SMB — the same footprint as standard SMB diodes, so no layout surprise if you are swapping in from another brand. The operating temperature range spans -55°C to 150°C junction, which covers most industrial and automotive ambient conditions without derating concerns at the board level.