SM340A
FUXINSEMI
Needs validationlow risk
A 40V, 3A Schottky diode in the same SMA package with nearly identical electrical characteristics.
Best Alternatives to B340A
The B340A is a popular 40V, 3A Schottky diode in a compact SMA package, used for rectification and freewheeling in power circuits. Several alternatives exist with similar or improved characteristics.
AI replacement insight
Electrical riskmedium
Ensure forward voltage (Vf) and reverse leakage are comparable to avoid thermal or performance issues.
Package risklow
The DO-214AC (SMA) package is standard, but verify land patterns as some alternatives have SMC variants.
Can it be replaced directly?
Direct replacement for B340A should use only Datasheet verified or Strong match candidates; many approved options still require engineering review.
Best replacement path
Use SM340A for a direct replacement or SS56 for a robust upgrade with higher voltage and current ratings.
Main risk
The main risk is selecting a part with a higher forward voltage (Vf), which increases power dissipation and could lead to thermal issues.
Recommended alternatives
3Alternative comparison matrix
| Feature / factor | B340A | SM340A | SS56 | SS54 | Compatibility / risk |
|---|---|---|---|---|---|
| Package | DO-214AC (SMA) | DO-214AC (SMA) | - | - | DO-214AC (SMA) — Same package. One variant (TWGMC) is SMC, ensure SMA version is sourced. |
| Voltage | 40V | 40V | - | - | 40V — Reverse voltage matches. |
| Current | 3A | 3A | - | - | 5A — Higher current rating provides more design margin. |
| Forward Voltage | 0.55V | 0.5V @ 3A | - | - | 0.55V @ 5A — Vf is comparable, good performance. |
Application & sourcing insights
Questions & answers
Verified drop-in options for B340A are limited in the current batch. Review candidates marked Strong match or Datasheet verified, and validate package, pinout, and electrical limits before committing a BOM change.