贴片晶体管一般以功率、频率分类。按频率一般可分为低频、高频和超高频三类;按功率一般可分为小功率、中功率和大功率三类。在使用中功率和大功率晶体管时,为达到要求的输出功率,一般要加散热片。因此,大功率晶体管一般不是贴片晶体管。一般而言,晶体 Chip transistor generally power, frequency classification. According to the frequency can generally be divided into three categories: low frequency, high frequency and ultra-high frequency; according to the power can generally be divided into small power, medium power and high power three categories. In the use of power and high-power transistors, in order to achieve the required output power, generally add heat sink. Therefore, high-power transistors are generally not SMD transistors. In general, crystals