Application analysis of field-effect transistors in audio digitization 5

In fact, compared with bipolar transistors, MOS transistors have excellent high-frequency characteristics and distortion mainly caused by even harmonics. Due to the absence of secondary breakdown phenomenon, Hitachi provides that the application current of MOS transistors such as K135/J50 can approach the recommended limit. The linear current of VMOS transistor can reach tens of amperes, and the pulse current of UHC-MOS transistors is even higher than 300A. So why is MOS sound tube misunderstood as having high current linearity difference? The fundamental reason is still a lack of sufficient understanding and corresponding countermeasures for the power loss caused by the internal resistance of MOS transistors. Although the internal resistance of VMOS and UHC-MOS transistors is very small, the V under high current can be as high as 5V or more, so they should also be taken seriously.

3. Improvement of MOSFET output stage efficiency

The loss of MOS power output stage is always greater than that of bipolar transistors, which is determined by its inherent characteristics. The improvement mentioned here should actually be how to reduce the power loss of MOSFET output stage.