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Schottky diode have a low forward voltage drop (typically \$0.15-0.45V\$) and very fast switching action, as compared to traditional diode, which typically have a \$0.7V\$ voltage drop (Silicon diodes). What is then the advantage of traditional diode as compared to Schottky diodes?

Alexandre Willame
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    They're cheaper! – Nick Johnson Dec 18 '14 at 16:43
  • Not enough for an answer, but in one application when I used diodes for a simple bridge rectifier, traditional silicon diodes proved to be better due to their higher voltage drop, because the result was lower power dissipation in the voltage regulator. – AndrejaKo Dec 18 '14 at 16:49
  • Schottky: More costly. If you need high voltage, the Vf advantage quickly decreases (20V <10ns 1N5817 0.45V@1A 40V 1N5819 0.6V@1A vs. 400V 50ns UF4004 1.0V@1A) so it pretty much disappears by 100V. Reverse leakage can be very high, esp. at high temperatures. Ultrafast high voltage diodes and gold doped diodes can be an advantage. – Spehro Pefhany Dec 18 '14 at 19:26

2 Answers2

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Full semiconductor junction diodes have much lower reverse leakage. Take a look at a Schottky diode datasheet, and note the reverse leakage, particularly at maximum working temperature.

Semiconductor junction diodes are also available at much higher reverse voltages.

Alexandre Willame
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Olin Lathrop
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Schottky diodes typically have much higher reverse leakage currents than traditional diodes.

Dave Tweed
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  • Hmm I assume the leakage current goes hand in hand with the lower barrier height. (It takes less thermal energy to make a carrier.) – George Herold Dec 18 '14 at 17:32