SMD marking code “B” — candidate parts
Small packages rarely print the full part number. The marking below maps to these part numbers — verify against the package, pin count and the manufacturer's datasheet before ordering.
Candidate part numbers
| Part number | Manufacturer | Package | Mapping basis | |
|---|---|---|---|---|
| BAS16-03W | INFINEON | SOD-323 | Public marking directory | |
| BB555 | INFINEON* | — | Public marking directory | |
| MBRX02540 | MCC | SOD-323 | Public marking directory | |
| MRF957 | MOT | SOT323 | Public marking directory | |
| RB520S-30 | MICRO COMMERCIAL COMPONENTS | SOD-523 | Public marking directory | |
| RB520S-40 | MCC | SOD-523 | Public marking directory | |
| UNRL113 | PANASONIC* | ML4 31tm - 2b Pan | Public marking directory | |
| UNRL213 | PANASONIC* | ML4 31tm - 2b Pan | Public marking directory | |
| 3SK302 | — | SOT-143 | Public marking directory | |
| 3SK306 | — | SOT-343 | Public marking directory | |
| CH3904T1PT | — | FBPT-523 17ta - 9a Chm | Public marking directory | |
| CH3904TPT | — | SOT-416 16ta - 3a Chm | Public marking directory | |
| EP05Q06 | — | SOD-123 | Public marking directory | |
| GBLC08I | — | SOD-323 | Public marking directory | |
| Si1013X | — | SC-89 | Public marking directory |
How these mappings are compiled: from public SMD marking directories and from our own stock records (marked Stock-record verified). We keep the original reference of every row internally so any mapping can be traced on request.
Markings are indicative only: the same code can denote different parts across manufacturers and packages. Always confirm with the physical batch marking and the original datasheet.
* Manufacturer derived from the part-number family (some directory entries carry no manufacturer) — treat it as a lead, not a datasheet fact.
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