PNDS / Marking codes / F3

Identify an unknown SMD part: marking code “F3”

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 22 with manufacturer source-traceable

Candidate part numbers

Part number	Manufacturer	Package	Mapping source
1SS193	TOS	SC-59	Public marking directory
1SS193	MCC	SOT-23	Public marking directory
2SC2814-3	TOS ^*	SOT-23	Public marking directory
2SC4399-3	TOS ^*	SOT-323	Public marking directory
BZX585-C3V0	PHI	SOD-523	Public marking directory
CMOZ3V0	CSC CENTRAL SEMIC.CORP. ^*	SOD-523	Public marking directory
HSMP-3823	AGILENT	SOT-23	Public marking directory
KST1009-F3	FSC ^*	SOT-23	Public marking directory
MMBC1009F3	MOT	SOT-23	Public marking directory
MMSZ5238B	DIODES	SOD-123	Public marking directory
MMSZ5238BS	DIODES	SOD-323	Public marking directory
MMSZ5238BS	DIODES	—	Public marking directory
MMSZ5239B	DIODES	—	Public marking directory
MMXZ5239B	MCC	SOD-323	Public marking directory
R3111N532A	RICOH ^*	SOT-23	Public marking directory
R3113D231C	RICOH ^*	—	Public marking directory
R3114Q101C	RICOH ^*	SC-82AB	Public marking directory
R5421N173C	RICOH ^*	SOT-23-6	Public marking directory
RN1904FS	TOS	—	Public marking directory
TC1073-3.0VCH	MIC ^*	SOT-23-6	Public marking directory
TC54VC5302ECB	MIC ^*	SOT-23	Public marking directory
TC54VC5302MB	MIC ^*	SOT-89	Public marking directory
ELM7623HBB	—	SOT-23 16vdc VD7 3d Elm	Public marking directory
FFM103-MH	—	SOD-123H	Public marking directory
FRS1D	—	DO-214AC	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 “F”

F F0 F1 F2 F4 F5 F6 F7 F8 F9

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.