Common parameters of rectifier diodes

Common parameters of rectifier diodes

(1) rectifier diodes Average rectification current IF: refers to the average forward current allowed to pass through a diode during long-term operation. The current is determined by the junction area and heat dissipation conditions of the PN junction. When using, it should be noted that the average current passing through the diode should not exceed this value and meet the heat dissipation conditions.

(2) rectifier diodes Reverse working voltage VR: refers to the reverse voltage allowed to be applied at both ends of the diode. If it is greater than this value, the reverse current (IR) will increase sharply, and the unidirectional conductivity of the diode will be destroyed, leading to reverse breakdown. Usually, half of the reverse breakdown voltage (VB) is taken as (VR).

(3) Reverse current IR: It is the reverse current allowed to flow through a diode under reverse operating voltage, which reflects the unidirectional conductivity of the diode. Therefore, the smaller the current value, the better the quality of the diode.

(4) rectifier diodes Breakdown voltage VR: refers to the voltage value at the point where the reverse volt-ampere characteristic curve of a diode sharply bends. When reverse is a soft characteristic, it refers to the voltage value under a given reverse leakage current condition.

(5) Working frequency fm: It is the working frequency of the diode under normal conditions. Mainly determined by the junction capacitance and diffusion capacitance of the PN junction, if the operating frequency exceeds fm, the unidirectional conductivity of the diode will not be well reflected.

(6)  rectifier diodes Reverse recovery time tre: Refers to the reverse recovery time under the specified load, forward current, and reverse transient voltage.

(7) rectifier diodes Zero bias capacitor CO: refers to the sum of the diffusion capacitance and junction capacitance when the voltage at both ends of the diode is zero. It is worth noting that due to manufacturing process limitations, even the same model of diode has significant parameter dispersion. The parameters given in the manual are often within a range, and if the testing conditions change, the corresponding parameters will also change.