(1) Maximum average rectified current if: refers to the maximum forward average current allowed by the diode during long-term operation. The current is determined by the junction area of the PN junction and the heat dissipation conditions. During use, it shall be noted that the average current through the diode shall not be greater than this value, and the heat dissipation conditions shall be met. For example, the if of the 1n4000 series diode is 1a.
(2) Maximum reverse working voltage VR: refers to the maximum reverse voltage allowed to be applied across the diode. If it is greater than this value, the reverse current (IR) increases sharply, and the unidirectional conductivity of the diode is destroyed, thereby causing reverse breakdown. Generally, half of the reverse breakdown voltage (VB) is taken as (VR). For example, the VR of 1N4001 is 50V, that of 1n4002-1n4006 is 100V, 200V, 400V, 600V and 800V respectively, and that of 1N4007 is 1000V
(3) Maximum reverse current IR: it is the reverse current allowed to flow through the diode under the highest reverse working voltage. This parameter reflects the unidirectional conductivity of the diode. Therefore, the smaller the current value, the better the quality of the diode.
(4) Breakdown voltage VB: refers to the voltage value at the sharp bending point of the diode reverse volt ampere characteristic curve. When the reverse is a soft characteristic, it refers to the voltage value under the given reverse leakage current condition.
(5) Maximum operating frequency FM: it is the highest operating frequency of the diode under normal conditions. It is 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. For example, the FM of the 1n4000 series diode is 3 kHz. In addition, the fast recovery diode is used for rectifying AC power with high frequency, such as switching power supply.
(6) Reverse recovery time TRR: refers to the reverse recovery time under the specified load, forward current and maximum reverse transient voltage.
(7) Zero bias capacitance Co: refers to the sum of diffusion capacitance and junction capacitance when the voltage across the diode is zero. It should be noted that due to the limitation of manufacturing process, even the same type of diode has a large dispersion of its parameters. The parameters given in the manual are often within a range. If the test conditions change, the corresponding parameters will also change. For example, the IR of 1n5200 series silicon plastic encapsulated rectifier diode measured at 25 ° C is less than 10uA, while the IR is less than 500uA at 100 ° C.
