PNDS / Marking codes / BF

Identify an unknown SMD part: marking code “BF”

Packages rarely print the full part number. The marking below is shared by several part numbers — use the package, pin count and the manufacturer family together to narrow it down, then confirm against the datasheet.

25 candidates 19 with manufacturer source-traceable

Candidate part numbers

Part number	Manufacturer	Package	Mapping source
1SS268	TOS	SOT-23	Public marking directory
1SS312	TOS	SOT-23	Public marking directory
1SS364	TOS	SOT-23	Public marking directory
BCW61FF	INFINEON	SOT23	Public marking directory
BCX55-6	INFINEON	SOT-89	Public marking directory
BD4724G	ROHM ^*	—	Public marking directory
BZX399-C7V5	PHI	SOD-323	Public marking directory
BZX399-C7V5	PHI	SC-76/SOD323	Public marking directory
BZX399C7V5	PHI	SOD323	Public marking directory
MAX822LUS-T	MAX ^*	SOT-143	Public marking directory
MAZD051	PANASONIC ^*	—	Public marking directory
MMBZ5246B	FSC	SOT-23 16dc - 3a Lge	Public marking directory
P6SMBJ13C	LITTLE ^*	DO-214AA	Public marking directory
R3112Q151A	RICOH ^*	SC-82AB	Public marking directory
R5421N136C	RICOH ^*	SOT-23-6	Public marking directory
RN5RT35AA	RICOH ^*	SOT-23-5	Public marking directory
UDZ7V5B	DIODES	SOD-323	Public marking directory
UDZ8V2B	DIODES	—	Public marking directory
V6300FSP5B	EMMICROELECTRONICS	SOT-23-5	Public marking directory
2SC3440-F	—	SC-59	Public marking directory
2SC3443-F	—	SOT-89	Public marking directory
AP432IAR	—	SOT-23-3L	Public marking directory
BCX55-06	—	SOT-89	Public marking directory
BZT52-C7V5S	—	SOD-323	Public marking directory
BZT52H-C7V5	—	SOD123F	Public marking directory

How we narrow this down

Package first — SOT-23 vs SOD-123 vs SC-59 eliminates most candidates immediately.
Pin count and body size — a 3-pin SOT-23 LDO cannot be a 6-pin dual transistor.
Marking style — laser-marked parts are usually newer production; ink marking often indicates older or second-source vendors.
Circuits around it — a part sitting on a rail with an inductor is a regulator, not a diode.
Datasheet check — every credible candidate lists its marking scheme in the “marking information” section.

FAQ

Same code, several parts — which one do I actually have? Compare package + pin count + surrounding circuit; if it still fits two parts, request a sample verification before production.
Can I substitute between the candidates? No — the same marking may sit on electrically different parts. Always match the electrical spec sheet, not just the marking.
Where do these mappings come from? Public SMD marking directories and historical stock tables; each row keeps its source so you can trace it.

Other codes starting with “B”

B1 B2 B3 B4 B5 B6 B7 B8 B9 BA

Still not sure what the part is?

Send the code, package and a photo through the BOM hub — our engineers cross-check it against datasheets and sourcing records.

How these mappings are compiled: public SMD marking directories plus our own stock records. Each row keeps its original reference internally, so any mapping can be traced on request. ^* Manufacturer derived from the part-number family (some directory entries carry no manufacturer) — treat it as a lead, not a datasheet fact. Markings are indicative only — confirm with the physical batch marking and the original datasheet before ordering.