The packaging form of the transistor is usually marked on the casing of the transistor, and different packaging forms have different marking methods.
Generally speaking, the packaging forms and marking methods of transistors are as follows:
1. TO-92 package: This package form is one of the most common transistor packages. Its marking method is to print model, polarity, numerical values and other identifications on the outer shell. Among them, the model number indicates the type and purpose of the transistor, the polarity indicates the pin sequence of the transistor, and the numerical value indicates the specifications of the transistor.
2. TO-220 package: This package form is usually used for power transistors and high-current transistors. The marking method is to print model, polarity, numerical values and other identifications on the outer shell. Among them, the model number indicates the type and purpose of the transistor, the polarity indicates the pin sequence of the transistor, and the numerical value indicates the specifications of the transistor.
3. SOT-23 package: This package form is usually used for low-power transistors, and its marking method is to print model, polarity and other marks on the outer shell. Among them, the model number indicates the type and purpose of the transistor, and the polarity indicates the pin sequence of the transistor.
4. SOT-89 package: This package form is usually used for high-power transistors, and its marking method is to print model, polarity and other marks on the outer shell. Among them, the model number indicates the type and purpose of the transistor, and the polarity indicates the pin sequence of the transistor.
In addition to the above common packaging forms and marking methods, there are also other packaging forms and marking methods, such as TO-3P, TO-247, SOT-25, etc. Different packaging forms and marking methods may be different, but their purpose is to facilitate users to identify and use transistors.