PNDS / Marking codes / BQ

Identify an unknown SMD part: marking code “BQ”

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
2PB709AQ	PHI	SC-59	Public marking directory
2PB709AQ	PHI	SC-59/SOT346	Public marking directory
2SB1218A-Q	PANASONIC ^*	SOT-323	Public marking directory
2SC2412-Q	MCC	SOT-23	Public marking directory
2SC4081-Q	MCC	SC-70	Public marking directory
2SC4081-R	MCC	SOT-323	Public marking directory
2SC4617-Q	MCC	SOT-416	Public marking directory
2SC4617-R	MCC	SOT-523	Public marking directory
BD4735G	ROHM ^*	—	Public marking directory
BZX399-C18	PHI	SOD-323	Public marking directory
BZX399-C18	PHI	SC-76/SOD323	Public marking directory
BZX399C18	NXP	SOD323	Public marking directory
P6SMBJ17C	LITTLE ^*	DO-214AA	Public marking directory
R1112N341A	RICOH ^*	SOT-23-5	Public marking directory
R3112Q141C	RICOH ^*	SC-82AB	Public marking directory
2SB1627-Q	—	SC-75	Public marking directory
2SB766A-Q	—	SOT-89	Public marking directory
2SC2412K-Q	—	SOT-346	Public marking directory
2SC5658-Q	—	—	Public marking directory
BZT52H-C18	—	SOD123F	Public marking directory
L2SC2412KQLT1	—	SOT-23	Public marking directory
P4SMA30	—	DO-214AC	Public marking directory
RT9169-34CV	—	SOT-23	Public marking directory
RT9169-35CX	—	SOT-89	Public marking directory
TV04A170K	—	DO-214AC	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 “B”

B1 B2 B3 B4 B5 B6 B7 B8 B9 BA

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.