What the key ratings mean for your BOM
The SMBJ33AQ-13-F: Breakdown voltage (VBR) is specified at 36.7V minimum, ensuring the device begins to clamp before the protected circuitry's absolute maximum rating is reached.
Housed in the DO-214AA (SMB) package, the device is surface-mount and occupies a standard footprint — the SMB body is larger than the SMA variant, offering better thermal dissipation for the 600W pulse rating. The unidirectional configuration (single channel) means the cathode band must be oriented toward the positive rail for proper clamping; reverse insertion results in forward conduction at low voltage.