The semiconductor triode, also known as the transistor, can be said to be the most important device in electronic circuits. Its main function is current amplification and switching. A triode, as its name suggests, has three electrodes. The diode is composed of a PN structure, and the triode is composed of two PN structures, and a common electrode becomes the base of the triode (represented by the letter b). The other two electrodes are the collector (represented by the letter c) and the emitter (represented by the letter e). Due to different combinations, one is an NPN type triode, and the other is a PNP type triode.
There are many types of triodes, and different models have different uses. Most of the triodes are plastic or metal packages. The appearance of common triodes is that the electrode with an arrow is the emitter, the arrow facing outwards is an NPN type triode, and the arrow facing inward is a PNP type. Actually the direction the arrow points is the direction of the current.
Commonly used transistors in electronic production are 90×× series, including low-frequency low-power silicon tube 9013 (NPN), 9012 (PNP), low-noise tube 9014 (NPN), high-frequency low-power tube 9018 (NPN) and so on. Their models are generally marked on the plastic case, and they all look the same, all of which are TO-92 standard packages. In old-fashioned electronic products, you can also see 3DG6 (silicon NPN high-frequency low-power transistor), 3AX31 (low-frequency low-power germanium tube), etc., and their models are also printed on the metal casing. The transistors produced in our country have a set of naming rules, and electronic engineering technicians and electronic enthusiasts should understand the meaning of the triode symbol.
The first part of the symbol "3" represents a triode. The second part of the symbol indicates the material and structure of the device: A—PNP type germanium material; B—NPN type germanium material; C—PNP type silicon material; D—NPN type silicon material. The third part of the symbol indicates the function: U——photoelectric tube; K——switch tube; X——low frequency low power tube; G——high frequency low power tube; D——low frequency high power tube; A——high frequency High power tube. In addition, the 3DJ type is a field effect transistor, and the BT head indicates a special semiconductor component.
There are many types of triodes, and different models have different uses. Most of the triodes are plastic or metal packages. The appearance of common triodes is that the electrode with an arrow is the emitter, the arrow facing outwards is an NPN type triode, and the arrow facing inward is a PNP type. Actually the direction the arrow points is the direction of the current.
Commonly used transistors in electronic production are 90×× series, including low-frequency low-power silicon tube 9013 (NPN), 9012 (PNP), low-noise tube 9014 (NPN), high-frequency low-power tube 9018 (NPN) and so on. Their models are generally marked on the plastic case, and they all look the same, all of which are TO-92 standard packages. In old-fashioned electronic products, you can also see 3DG6 (silicon NPN high-frequency low-power transistor), 3AX31 (low-frequency low-power germanium tube), etc., and their models are also printed on the metal casing. The transistors produced in our country have a set of naming rules, and electronic engineering technicians and electronic enthusiasts should understand the meaning of the triode symbol.
The first part of the symbol "3" represents a triode. The second part of the symbol indicates the material and structure of the device: A—PNP type germanium material; B—NPN type germanium material; C—PNP type silicon material; D—NPN type silicon material. The third part of the symbol indicates the function: U——photoelectric tube; K——switch tube; X——low frequency low power tube; G——high frequency low power tube; D——low frequency high power tube; A——high frequency High power tube. In addition, the 3DJ type is a field effect transistor, and the BT head indicates a special semiconductor component.
