PNDS / Marking codes / K5

Identify an unknown SMD part: marking code “K5”

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
2SC3143-5	TOS ^*	SOT-23	Public marking directory
2SK853-5	TOS ^*	SOT-323 16fa - 3a Nec	Public marking directory
BCW72R	MOT	SOT-23	Public marking directory
BZX384-B3V6	PHI	SOD-323	Public marking directory
MAX810RTR	MAX	SOT-23	Public marking directory
MMBZ5255B	FS	SOT-23	Public marking directory
MMBZ5255BW	DIODES	SOT-323	Public marking directory
MMSZ5252B	FSC	SOD-123	Public marking directory
MMSZ5255B	MCC	SOD-123	Public marking directory
MMSZ5255BS	DIODES	SOD-323	Public marking directory
MMSZ5255BS	DIODES	—	Public marking directory
MMSZ5256B	DIODES	—	Public marking directory
MMXZ5256B	MCC	SOD-323	Public marking directory
R3111N252C	RICOH ^*	SOT-23	Public marking directory
R5426D105DA	RICOH ^*	—	Public marking directory
R5426N105DA	RICOH ^*	SOT-23-6	Public marking directory
RN2966FS	TOS	—	Public marking directory
RN5RG35AA	RICOH ^*	SOT-23-5	Public marking directory
RN5RY251A	RICOH ^*	SOT-23-5	Public marking directory
2SK160-5	—	SC-59 16fh - 3a Nec	Public marking directory
BAP63-02	—	SOD-523	Public marking directory
ELM7645HAB	—	SOT-23 16vdc VD7 3d Elm	Public marking directory
MMSZ52355	—	SOD-123	Public marking directory
R1111N151B	—	SOT-23-5	Public marking directory
RP103Q331D	—	SC-82AB	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 “K”

K1 K2 K4 KB KC KD KE KEC KM KN

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.