PNDS / Marking codes / AD

Identify an unknown SMD part: marking code “AD”

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
12A02CH	ON	CPH3 16ta - 3a San	Public marking directory
BCP51-16	PHI	SOT-223	Public marking directory
BCW60D	PHI	SOT23	Public marking directory
BCX51-16	INFINEON	SOT-89	Public marking directory
BCX51-16	PHI	SC-62/SOT89	Public marking directory
BCX51-160	INFINEON	SOT89	Public marking directory
BCX55	MCC	SOT-89	Public marking directory
MAX6314US47D1-T	MAX ^*	SOT-143	Public marking directory
MMBZ5228B	FSC	SOT-23 16dc - 3a Lge	Public marking directory
MMSZ5233B	DIODES	SOD-123	Public marking directory
MT3S07S	TOS ^*	SOT-23	Public marking directory
P6SMBJ5.0C	LITTLE ^*	DO-214AA	Public marking directory
RN5RT23AA	RICOH ^*	SOT-23-5	Public marking directory
XP01110	PANASONIC ^*	SMini5	Public marking directory
ZMV832A	ZETEX	SOD-323	Public marking directory
2SD1366A-AD	—	SOT-89	Public marking directory
2SD1366A-D	—	SOT-89	Public marking directory
74AHC1GU04	—	SC-88A	Public marking directory
AP431IAW	—	SOT-23-3L	Public marking directory
BZX884-B7V5	—	SOD-882	Public marking directory
ELM99231B	—	SOT-89	Public marking directory
GS6333UR15D1	—	SOT-23	Public marking directory
KDZ20B	—	—	Public marking directory
MAZU220-H	—	SOT-346	Public marking directory
P4SMA6.8	—	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 “A”

AL AH-16 A1 A2 A3 A4 A5 A6 A7 A8

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.