
onsemi
SMMBT3906LT1G is a lower-rated PNP BJT candidate for low-stress circuits.
MMBT5401LT1G is a high-voltage PNP BJT. Most recalled parts are JFETs and are not valid substitutes.
Candidate BJT is lower rated.
SOT-23 text matches.
Discrete transistor.
Kept candidate is active.
No proven pin-compatible replacement is supported by the provided evidence.
Use a PNP BJT with equal or higher VCEO, IC, package, and verified pinout.
Voltage and current underrating.

onsemi
SMMBT3906LT1G is a lower-rated PNP BJT candidate for low-stress circuits.
| Feature / factor | MMBT5401LT1G | SMMBT3906LT1G | Alt 2 | Alt 3 | Compatibility / risk |
|---|---|---|---|---|---|
| Package | SOT-23 | SOT-23 | SOT-23 — Same package text | ||
| Pinout | 3-pin PNP | 3-pin PNP | 3-pin PNP — Pin functions not shown | ||
| Voltage | -150 V VCEO | -40 V VCEO | -40 V VCEO — Not HV rated | ||
| Current | -500 mA | -200 mA | -200 mA — Lower IC rating | ||
| Temperature | -55 to 150 C | -65 to 150 C | -65 to 150 C — Range covers target |
None is proven from this set. A replacement should be a PNP BJT with at least 150 V VCEO and 500 mA IC.