PNDS / Marking codes / M8

Identify an unknown SMD part: marking code “M8”

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
2SC5091-O	TOS	SC-70	Public marking directory
2SC5091F-O	TOS ^*	TESM 18ta - 3a Tos	Public marking directory
2SC5091FT-O	TOS ^*	—	Public marking directory
BSH103	PHI	SOT-23	Public marking directory
BSS66R	FERRANTI	SOT-23	Public marking directory
BZX384-B27	PHI	SOD-323	Public marking directory
BZX84C4V7	FSC	SOT-23 16dc - 3a Lge	Public marking directory
CMOZ4L7	CSC CENTRAL SEMIC.CORP.	SOD-523	Public marking directory
ILC5061IC28X	FSC ^*	SC-70	Public marking directory
ILC5061M28X	FSC ^*	SOT-23	Public marking directory
MM5Z8V2	FSC	SOD-523	Public marking directory
R1121N381A	RICOH ^*	SOT-23-5	Public marking directory
R3111N482C	RICOH ^*	SOT-23	Public marking directory
R3111Q281A	RICOH ^*	SC-82AB	Public marking directory
R3116Q251A	RICOH ^*	SC-82AB	Public marking directory
RN5RG58AA	RICOH ^*	SOT-23-5	Public marking directory
RN5RY481A	RICOH ^*	SOT-23-5	Public marking directory
TC54VN2802ECB	MIC ^*	SOT-23	Public marking directory
TC54VN2802MB	MIC ^*	SOT-89	Public marking directory
ELM7638LAB	—	SOT-23 16vdc VD7 3d Elm	Public marking directory
R1100D181C	—	—	Public marking directory
R1131D181B	—	—	Public marking directory
R1151N009C	—	SOT-23-6	Public marking directory
RP104Q221B	—	SC-82AB	Public marking directory
RT9168A-23CBR	—	SOT-23-5	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 “M”

MEV MK7 M1 M2 M3 M4 M5 M6 M7 M9

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.