Key parameters of Schottky diodes

Key parameters of Schottky diodes

Schottky diodes are widely used in circuits such as switching power supplies, frequency converters, and drivers. In different applications, different factors need to be considered, and different devices also have differences in performance,

Therefore, when selecting Schottky diodes, the following key parameters need to be comprehensively considered.

1. The conduction voltage drop (VFVF) is the voltage drop at both ends of the diode when it is conducting forward. The greater the current passing through the diode, the greater the VF; The higher the diode temperature, the smaller the VF.

2. Reverse saturation leakage current (IRIR) refers to the current flowing through the diode when a reverse voltage is applied at both ends of the diode. The Schottky diode has a higher reverse leakage current, so choosing a Schottky diode is to try to choose a diode with a smaller IR.

3. Rated current IF refers to the average current value calculated based on the allowable temperature rise during long-term operation of a Schottky diodes.

4. The excessive forward current allowed by the maximum surge current IFSM. It is not a normal current, but an instantaneous current, which is quite large.

5. The maximum reverse peak voltage VRM, even if there is no reverse current, as long as the reverse voltage is continuously increased, sooner or later the diode will be damaged. The reverse voltage that can be applied is not an instantaneous voltage, but a repeatedly applied forward and reverse voltage.

Due to the AC voltage applied to the rectifier, its maximum value is a specified important factor. The maximum reverse peak voltage VRM refers to the maximum reverse voltage that can be applied to avoid breakdown. At present, the highest VRM value for Schottky diodes is 150V.