Discrete
Schottky Diodes (SKY)
Low-forward-drop, fast diodes for power rectification and low-loss steering.
What is it?
A Schottky diode uses a metal-semiconductor junction instead of a P-N junction. Result: lower forward voltage (0.2-0.5 V vs 0.7 V silicon) and no reverse-recovery time. Trade-off: higher reverse leakage and lower reverse voltage capability. Schottky is the diode of choice wherever low conduction loss matters — power converter output rectifiers, OR-ing diodes for redundant supplies, RF detectors.
When do you need it?
- Buck / boost converter output rectifier (sync rectifier replaces where efficiency really matters).
- Diode-OR for dual-supply redundancy (e.g., USB + barrel jack power).
- Reverse-polarity protection where every millivolt of drop counts.
- Solar-panel bypass diodes.
- RF / mixer detector diodes (very low VF Schottkys).
How to pick the right one
- Forward current (IF average / continuous)
- Must exceed continuous output current with thermal margin.
- Reverse voltage (VR)
- Must exceed maximum reverse voltage during converter switching. 40 V and 60 V common for buck outputs; up to 200 V for boost / flyback.
- Forward voltage at IF
- Lower = less conduction loss. Tradeoff: lower VF generally means higher leakage.
- Reverse leakage (IR)
- Can be significant at high temperature — check VR vs T curves.
- Package
- SOD-123 / 323 / 523 for low current (≤2 A), SMA / SMB / SMC for 3-10 A, TO-220 / TO-252 for higher.
What Magnias offers
Magnias Schottky portfolio covers 0.5 A to 10 A continuous, 20 V to 200 V reverse, in SOD / SMA / SMB / SMC / TO-252 packages. AEC-Q101 automotive grade available. Note: legacy SS320 and SD103AWS are EOL — please use current-generation equivalents.
Common questions
When should I use Schottky vs Fast Recovery Rectifier?
Schottky if VR ≤ ~150 V (above that, Schottky leakage gets bad). Fast Recovery for higher voltage (boost / flyback / PFC) where leakage matters more than VF.
Why is my Schottky running hot?
Reverse leakage. At high T, Schottky leakage can rise 100×, dissipating power continuously even when reverse-biased. Pick a lower-leakage variant or move to a fast-recovery silicon part.
Are SS320 and SD103AWS still available?
No — both EOL. Use current Magnias replacements; ask FAE for the latest cross.