PNDS / Marking codes / DU

Identify an unknown SMD part: marking code “DU”

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.

24 candidates 11 with manufacturer source-traceable

Candidate part numbers

Part number	Manufacturer	Package	Mapping source
BCW67BR	SGS	SOT23R	Public marking directory
BCW67RB	SIEMENS	SOT-23	Public marking directory
BD4838FVE	ROHM ^*	VSOF-5	Public marking directory
BD4838G	ROHM ^*	SSOP-5	Public marking directory
MAX6314US48D3-T	MAX ^*	SOT-143	Public marking directory
MMBZ4706	VISHAY ^*	SOT-23	Public marking directory
P4SMA200A	LITTELFUSE	DO-214AC	Public marking directory
P6SMBJ85C	LITTLE ^*	DO-214AA	Public marking directory
R3112Q381C	RICOH ^*	SC-82AB	Public marking directory
XC61119C35ANR-G	TOREX ^*	SSOT-24 26gh VD3 5c Tor	Public marking directory
XC6119C35ANR	TOREX ^*	SSOT-24	Public marking directory
3SK241	—	SOT-143	Public marking directory
AP131-35TW	—	—	Public marking directory
AP131-35W	—	SOT-23-5L	Public marking directory
AP131-35Y	—	SOT-89-5L	Public marking directory
BZX384-C56	—	SOD-323	Public marking directory
HQ1F2Q	—	SOT-89	Public marking directory
MMSZ4706	—	SOD-123	Public marking directory
R5220D281B	—	—	Public marking directory
RT9809-43CV	—	SOT-23 16vdc VD7 3a Rct	Public marking directory
TV06B850KB	—	DO-214AA	Public marking directory
XC6109C35AN	—	SSOT-24	Public marking directory
XC6127C45JNR	—	SSOT-24	Public marking directory
XC6127N46DNR	—	SSOT-24	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 “D”

D0 D1 D2 D3 D4 D5 D6 D7 D8 D9

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.