What 3F can be
3FBC857BPNP transistorSOT-23 · Nexperia · 45 V · 100 mA · hFE 220-475
Pins: 1=B 2=E 3=C
On the part, one more character can follow 3F: a date or factory code. datasheet
3FBC857BSDual PNP transistorSOT-363 · Nexperia · 45 V · 100 mA · hFE 200-450
Pins: 1=E1 2=B1 3=C2 4=E2 5=B2 6=C1
On the part, one more character can follow 3F: 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-363 | SC-70-6, SC-88 | 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-363 2 × 1.25 mm.
A multimeter in diode mode tells transistors apart: an NPN shows about 0.6–0.7 V from the base to both other pins with the red probe on the base; a PNP does the same with the black probe on the base.
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 |
|---|---|---|---|
| BC857 | 3H | PNP transistor | SOT-23 |
| BC857A | 3E | PNP transistor | SOT-23 |
| BC857AW | 3E | PNP transistor | SOT-323 |
| BC857C | 3G | PNP transistor | SOT-23 |
| BC857CW | 3G | PNP transistor | SOT-323 |
Frequently asked questions
What is the pinout of SMD code 3F?
BC857B (SOT-23): 1=B 2=E 3=C. BC857BS (SOT-363): 1=E1 2=B1 3=C2 4=E2 5=B2 6=C1.
Marking codes checked against the makers’ datasheets; each part links to its own.