Transistor although only one more than the diode foot, but function abnormally poor, our software engineers brothers do not too literally.
I learned in high school before electronic components are basically two feet, now a three foot, do not adapt. In fact, the situation is more than just an electronic foot are common, especially after we said integrated chip, more than 100 feet are also common, so there is no need to feel strange. Nothing like we were little experience, I feel the house should be only one door, go to the town grew up wealthy family to play, people have found two doors, and then later to the provincial capital officer people play, found upstairs downstairs each two doors, it is poverty limit imagination.
The main effect transistor amplification and switching, said first amplification.
To say that this transistor amplifier is really a landmark, and now every day we listen to the sound, for a zoom, a will decrease the volume, you know, this is not just resistance at work, more importantly, play a role in the transistor, this transistor has three feet, are called e, b, c, do not ask why is it called that, it is a symbol, and English related. The key is doing it all. The transistor corresponding to two lines (circuit), a line, is the ec, ec this circuit is a large current flows, the other one is be, be this circuit a small current is flowing, the transistor has such a characteristic when small changes occur in the current line be, drastic changes in the current ec lines occurs, it's not, the key is to change both in unison, this is important, for a period of professional hardware engineer the term is called the same waveform changes, it's a bit like telepathy, yes, that is telepathic, this situation can be found everywhere in our nature, so do not be surprised.
In this way, the amplifying transistor put waveform, the amplitude of the voltage and current is actually increased.
Besides transistor switching function. The transistor also has a feature that a voltage between the amplification can only be within a certain range (about 0.7 volts silicon tube), it would be outside of this range of the switch. That is not magnified. This feature is also very amazing, so we can use this feature to do the electronic switches the transistor. However, the actual product due to various reasons, do not use the transistor switch directly, usually with a transistor to control the relay, because relays can be directly connected to AC power, able to withstand larger current and voltage.
Transistor useful, there are many, we are in the future with specific application to say.
