PNDS / Marking codes / 8B

Identify an unknown SMD part: marking code “8B”

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 15 with manufacturer source-traceable

Candidate part numbers

Part number	Manufacturer	Package	Mapping source
2DA1774R	DIODES	SOT-523	Public marking directory
2DA1774S	DIODES	—	Public marking directory
DTC124EE	ROHM	SC-75	Public marking directory
MMBZ5227B	FSC	SOT-23	Public marking directory
MUN2212	MOT	SC-59	Public marking directory
MUN5212	MOT	SOT-323	Public marking directory
NJM78L03A	NJR NEW-JAPAN-RADIO	SOT89	Public marking directory
NJM78L03UA	NJR ^*	SOT-89	Public marking directory
R3111N181A	RICOH ^*	SOT-23-5	Public marking directory
RH5RL28AA	RICOH ^*	SOT-89	Public marking directory
RN5RL28AA	RICOH ^*	SOT-23-5	Public marking directory
RQ5RW31BA	RICOH ^*	SOT-143R	Public marking directory
UNR2212	PANASONIC ^*	SC-59	Public marking directory
UNR5212	PANASONIC ^*	SOT-523	Public marking directory
UNR9212J	PANASONIC	SC-89	Public marking directory
HA178L05UA	—	SOT-89	Public marking directory
HMBZ5227B	—	SOT-23	Public marking directory
KIA78L06F	—	SOT-89	Public marking directory
R1161D181A	—	—	Public marking directory
R3131N28EC	—	SOT-23	Public marking directory
R3132Q41EC	—	SOT-143	Public marking directory
RN5VD18CA	—	SOT-23-5	Public marking directory
UN2212	—	SC-59	Public marking directory
UN5212	—	SOT-523	Public marking directory
UN9212J	—	SC-89	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 “8”

8A 8C 8D 8E 8F 8H 8K 8L 8N 8P

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.