The hFE parameters of the transistor are related to the storage time ts, and generally, transistors with larger hFE have larger ts. In the past, people's understanding of ts and the measurement instruments for ts were relatively lacking, and people relied more on the hFE parameters to choose the transistor
Rectifier
In the switching state, the selection of hFE usually has the following understanding: firstly, hFE should be as high as possible to obtain the maximum working current with the minimum base current, while providing the lowest possible saturation voltage, so as to reduce losses in both the output and driving circuits.
However, if switching speed and current tolerance are considered, the maximum value of hFE is limited; Secondly, Chinese manufacturers once tended to choose devices with smaller hFE, such as transistors with hFE ranging from 10 to 15, or even 8 to 10, which were once very popular (later, due to the popularity of capacitor triggered circuits in the base circuit, the value of hFE increased). A small value of hFE resulted in a smaller saturation depth, which was beneficial for reducing transistor heatingFunction of testing report:
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