Unidirectional conductivity characteristic
The unilateral conductivity of diode makes it play an important role in many fields such as rectification, isolation and voltage stabilization. It is like a traffic policeman in a circuit, only allowing the current to pass in the forward direction and resolutely stopping it in the reverse direction.
Application in telephone
In telephone, diode is indispensable. Whether it is rectification, isolation or voltage stabilization, it can be competent. Moreover, there are many kinds of diodes in the phone, each of which has its own unique purpose.
Identification diode
How to identify diodes? Actually, it's very simple! Just looking at its appearance, the N pole (negative pole) is usually marked with a colored circle. Light emitting diodes are easier. The long needle is the positive pole and the short needle is the negative pole.
Testing skills
When testing, remember to connect the red probe of the digital multimeter to the anode of the diode and the black probe to the cathode, so as to get the accurate positive on resistance!
Withstand voltage information
Finally, I will give you some common information about withstand voltage of 1N4000 series diodes. From 1N400 1 to 1N4007, the withstand voltage varies from 50V to 1000V, and the current is1a. Choose according to the actual needs!