What A1 can be
A1AO3401P-channel MOSFETSOT-23 · Alpha & Omega Semiconductor · 30 V · 4 A · RDS(on) 50 mΩ at 10 V
Pins: 1=G 2=S 3=D
On the part, up to 4 more characters can follow A1: a date or factory code. datasheet
A1BAW56Dual switching diodeSOT-23 · Nexperia · 90 V · 215 mA
Pins: 1=K1 2=K2 3=A
On the part, one more character can follow A1: a date or factory code. datasheet
A1BAW56WDual switching diodeSOT-323 · Nexperia · 90 V · 150 mA
Pins: 1=K1 2=K2 3=A
On the part, one more character can follow A1: a date or factory code. datasheet
Package size
| Package | Also called | Body | Height |
|---|---|---|---|
| SOT-23 | TO-236AB, SOT-23-3 | 2.9 × 1.3 mm | 1 mm |
| SOT-323 | SC-70, SC-70-3 | 2 × 1.25 mm | 0.95 mm |
Nominal body size without the leads.
How to tell them apart
Measure the plastic body without the leads: SOT-23 2.9 × 1.3 mm · SOT-323 2 × 1.25 mm.
In diode mode a MOSFET shows only its body diode, between source and drain and in one direction; nothing answers from the gate.
The same code can mean different parts at different makers. The package narrows it down, so measure the body.
Open the SMD identifier →Not sure it is this part? Enter the marking with the shape and size of the body: the identifier checks it against all 340 markings in the database.
Related parts and their markings
| Part | Marking | Type | Package |
|---|---|---|---|
| AO3401A | X1 | P-channel MOSFET | SOT-23 |
Frequently asked questions
What is the pinout of SMD code A1?
AO3401 (SOT-23): 1=G 2=S 3=D. BAW56 (SOT-23): 1=K1 2=K2 3=A. BAW56W (SOT-323): 1=K1 2=K2 3=A.
Marking codes checked against the makers’ datasheets; each part links to its own.