PNDS / Marking codes / 3A

Identify an unknown SMD part: marking code “3A”

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 14 with manufacturer source-traceable

Candidate part numbers

Part number	Manufacturer	Package	Mapping source
2SC5472	NEC ^*	SOT-323	Public marking directory
2SC5473	NEC ^*	SOT-343	Public marking directory
2SC5474	NEC ^*	SOT-23	Public marking directory
BC856A	NXP	SOT-23	Public marking directory
BC856AS	DIODES	—	Public marking directory
BC856AT	NXP	SOT-416	Public marking directory
BC856AT	PHI	SC-75/SOT416	Public marking directory
BC856AW	PHI	SOT-323	Public marking directory
BC856B	MCC	SOT-23	Public marking directory
BGA6289	INFINEON ^*	SOT-89	Public marking directory
CH706F-40PT	CHRONTEL ^*	SOT-323 16dl - 3a Chm	Public marking directory
KST24	FSC	SOT-23	Public marking directory
MMBTH24	FSC	SOT23	Public marking directory
RQ5RW30AA	RICOH ^*	SOT-143R	Public marking directory
2SB1699	—	SOT-89	Public marking directory
MM3Z43V	—	SOD-323	Public marking directory
R3132Q40EA	—	SOT-143	Public marking directory
RF1	—	—	Public marking directory
VD6	—	—	Public marking directory
VD8	—	—	Public marking directory
VR1	—	—	Public marking directory
VR11	—	—	Public marking directory
VR16	—	—	Public marking directory
VR17	—	—	Public marking directory
VR7	—	—	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 “3”

30 33 36 37 39 3B 3E 3D 32 35

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.