SMD marking code “BC559B” — candidate parts
7 candidates3 with manufacturer
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 | |
|---|---|---|---|---|
| 4Bp | PHI | SOT23 | Public marking directory | |
| 4Bt | PHI | SOT23 | Public marking directory | |
| 4Dt | PHI | SOT323 | Public marking directory | |
| 4B- | — | SOT323 | Public marking directory | |
| 4BR | — | SOT23R | Public marking directory | |
| 4Bs | — | SOT23 | Public marking directory | |
| 4D- | — | SOT323 | 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.
Can't match your marking?
Send us the code, package and a photo — our team helps identify the part.
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