top of page
Este site foi desenvolvido com o criador de sites
.com
. Crie seu site hoje.Começar
DIODE

Their function is simple: to only let current pass through in one direction. We can think of the water pipe analogy we talked about previously: a diode is like a check valve. Here is the electronic symbol: 

The diode is the first true electronic component that was invented. At first it was shaped like a huge electronic tube, which was heated up a lot - but now - thankfully - it exists in several, much smaller forms:

The arrow shape is not a coincidence, the direction of the arrow indicates the direction of flow of electric current. In "normal" use, the diode lets the current pass when the anode is more positive than the cathode. The cathode is identified on a diode by a colored band (see image). 

A special form of the diode is the light-emitting diode, or LED. Its symbol:  

The two small arrows indicate that this diode emits light. Remember our assembly last week:

We can clearly see that the anode is positive and the cathode negative. (I know - it's not the good resistance value with a 3v power supply ...).  

If we reverse the LED, it does not light up anymore and the current does not flow anymore. 

 

References

bottom of page