How to test damage to Schottky diodes?

How to test damage to Schottky diodes?

Schottky diodes are indispensable in electronic materials and often encounter damage problems during use. Those who know about Schottky diodes know that their withstand voltage is relatively low, and their recovery speed is relatively fast. Therefore, they often appear in high-frequency situations. So how do I test if the Schottky  diode is damaged?

1. How to judge whether a Schottky diode is good or bad when it cannot be removed for inspection?

One method is to connect the power supply and measure its output voltage. If the output voltage or output voltage is abnormal, it will be damaged.

Two methods can measure the forward and reverse resistance of Schottky diodes without being charged, and the difference in resistance indicates a problem.

2. Detection of the Quality of Two Terminal Schottky diodes

The simplest method for this type of Schottky  diode is to use a digital multimeter to measure it, with the multimeter set to "R × 1 "gear detection, with the black lead connected to the positive pole and the red lead connected to the negative pole. When normal, its forward resistance value is 2.5~3.5 Ω, and the reverse resistance value is infinite. If the measured forward and reverse resistance values are both infinite or close to 0, it indicates that the Schottky  diode has been opened or damaged by breakdown.

3. Quality Detection of Three Terminal Schottky diode

This type of tube is a bit different from the first two. This Schottky  diode should first measure its common end, distinguish between a common negative or a common positive pair of tubes, and then measure the forward and reverse resistance values of the two tubes. Let's take a common negative pair tube and a common positive pair tube as examples to explain how to detect them in detail. Firstly, label the pins as l, 2, and 3, and place the multimeter in "R × Perform the following three step test for gear 1 ''.

① Measure the forward and reverse resistance values of pins 1 and 3. If it is infinite, it indicates that these two electrodes have no single conductivity.

② Connect the red lead to pin 2 and the black lead to pin 1. If the result is infinite, swap the black and red lead for detection. If the measured result is 2.5~3.5 Ω, it indicates that pins 2 and 1 have unidirectional conductivity, and pin 2 is positive and pin 1 is negative.

③ In the final step, connect the red lead to 2 pins and the black lead to 3 pins. If the result is infinite, swap the black and red lead for detection. If the measured result is 2.5~3.5 Ω, it indicates that pins 2 and 3 have unidirectional conductivity, and pin 2 is positive and pin 3 is negative. Based on the three measurement results mentioned above, we can determine that the Schottky  diode is a common anode pair tube, with pins 1 and 3 being two cathodes and pin 2 being a common anode. On the contrary, it is a common negative pair of tubes.