SOT is a patch type low-power transistor package, which mainly includes the following types:
1. SOT23. The volume is smaller than the TO package. It has three wing pins, namely collector, emitter and base, which are listed on both sides of the long side of the component. It is suitable for use in low-power transistors, field effect transistors and composite transistors with resistor networks. .
2. SOT89. It has three short pins distributed on one side of the transistor, and a metal heat sink on the other side connected to the base to increase heat dissipation. This kind of packaging is mainly suitable for silicon power surface assembly and high power applications.
3. SOT143. It has four short wing pins coming out from both sides, and the big end of the pins is the collector. This type of packaging is common in high frequency transistors.