PNDS / Marking codes / A9

Identify an unknown SMD part: marking code “A9”

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 11 with manufacturer source-traceable

Candidate part numbers

Part number	Manufacturer	Package	Mapping source
1SS294	TOS	SC-59	Public marking directory
1SS322	TOS	SC-70	Public marking directory
BAV20W	MCC	SOD-123	Public marking directory
BZX84C9V1	FSC	SOT-23 16dc - 3a Lge	Public marking directory
BZX884-B5V1	PHI	SOD-882	Public marking directory
MM5Z33V	FSC	SOD-523	Public marking directory
R3111N092A	RICOH ^*	SOT-23	Public marking directory
R3113D191A	RICOH ^*	—	Public marking directory
R3114Q161A	RICOH ^*	SC-82AB	Public marking directory
SI2309DS	SILICONIX-VISHAY	SOT23	Public marking directory
TC1014-3.6VRX	MIC ^*	SOT-23-5	Public marking directory
AP431AR	—	SOT-23-3L	Public marking directory
ELM9709NAB	—	SOT-89	Public marking directory
ELM9829AB	—	SOT-89	Public marking directory
FMA9A	—	SOT-23-5	Public marking directory
LM4916MM	—	—	Public marking directory
R1111N291A	—	SOT-23-5	Public marking directory
R1140Q191B	—	SOT-143R	Public marking directory
R1160D091A	—	—	Public marking directory
R1180Q191B	—	SC-82AB	Public marking directory
R3130N19EC	—	SOT-23	Public marking directory
RKV5020DKK	—	—	Public marking directory
RN5VD09AA	—	SOT-23-5	Public marking directory
RT9161-26CV	—	SOT-23	Public marking directory
Si2309DS	—	SOT-23	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.