What Is the 1N5819? Schottky Diode: Low Loss and Uses
The 1N5819 is a common Schottky diode. With a low forward drop (~0.45 V) and fast switching it is used where efficiency/speed matter: the catch diode in a buck regulator (e.g. the LM2596), low-loss rectification and reverse-polarity protection. Its reverse voltage is low (40 V); for high voltage you need the 1N4007.
The 1N5819 is a common Schottky diode. Schottky diodes have two advantages: a very low forward voltage drop (~0.45 V) and fast switching. So they replace ordinary rectifier diodes where efficiency and speed matter. For the concept, see what is a Schottky diode.
What is the 1N5819 used for?
The catch/freewheel diode in switching regulators (buck, e.g. the LM2596), low-loss rectification, reverse-polarity protection, OR-ing (combining multiple sources) and everywhere in low-voltage circuits. Its low drop matters for battery life and efficiency.
Key electrical specifications
| Parameter | Typical value |
|---|---|
| Type | Schottky diode |
| Reverse voltage (VR) | 40 V |
| Forward current (average) | 1 A |
| Forward drop (VF) | ~0.45 V (at 1 A) |
| Body | DO-41 |
Against a silicon diode's ~0.7 V (or a power diode's ~1 V) drop, ~0.45 V is a real efficiency gain in low-voltage systems.
Limitations
- Low reverse voltage (40 V); not for high-voltage rectification → the 1N4007.
- Schottky diodes have higher reverse leakage than ordinary diodes (which rises with temperature).
1N5819 equivalents and alternatives
- 1N5817 / 1N5818: the 20 V / 30 V members of the same family.
- SS14 / SS34: SMD Schottky alternatives (SS34 = 40 V, 3 A).
- SB560: a higher-current Schottky.
- 1N4007: if you need high voltage (but a high drop).
Find it in our catalog
To compare price and stock for the 1N5819 and its alternatives, use the 1N5819 search.