BSS138 N-MOSFET (SOT-23)
BSS138 · N-channel logic MOSFET · 50 V · 0.2 A · V_GS(th) ≈ 1.3 V · R_DS(on) ≈ 3.5 Ω at 2.5 V · body diode from source to drain makes the bidirectional I²C level shifter work
Try it on the benchThe lab drops it on an empty bench and opens its datasheet card.
Typical part: BSS138 N-channel MOSFET (SOT-23)
Pins
- G
- D
- S
Ratings and limits
| V_DS | 50 V |
|---|---|
| I_D | 0.22 A |
| V_GS(th) | 0.8–1.5 V |
| R_DS(on) | 3.5 Ω at V_GS = 2.5 V |
How to use it
The classic I²C level shifter: gate to 3.3 V, source to the 3.3 V side, drain to the 5 V side, a 10 kΩ pull-up on each side. Either side pulling low pulls the other low (directly or through the body diode).