ДОСЛіДЖЕННЯ ШУМОВИХ ХАРАКТЕРИСТИК БіПОЛЯРНОГО ТРАНЗИСТОРА В ОБЛАСТі СЕРЕДНіХ ЧАСТОТ

The article analyzes the noise characteristics of bipolar transistors for the medium-frequency range and suggests a method, which allows the additional evaluation of the characteristics of the bipolar transistors in the mediumfrequency range at the stages of input and output control according to the level of the low-frequency noise.All noise range was divided into three subranges with the division points f1 and f2. The equivalent noise model, which takes into account the thermal and fractional noises, as well as the change of the transistor modes during a checkout, was suggested for the range (f1, f2).The research has shown that the studied range would vary for the bipolar transistors of different types. It con-cerns, particularly, the upper limit of the frequency range f2. For the lower limit of the frequency, the significant changes are observed only in the low-noise transistors