Transistor circuit problem

Syber

Transistor circuit problem [Copy link]

If the value of Rc of the transistor is too large, the voltage drop of Rc itself will increase, the collector potential will decrease, and when the output amplitude is large, the collector potential will be close to the emitter potential, cutting off the lower side of the output waveform. On the contrary, if the value of Rc is too small, the collector potential will be close to the power supply potential, cutting off the upper side of the output waveform. How to understand this paragraph?

btty038

That's all I know.

maychang

"If the value of Rc of the transistor is too large... the lower side of the output waveform is cut off... If the value of Rc is too small... the upper side of the output waveform is cut off" This statement is incorrect. For a certain collector load resistance Rc, a collector static current value can be selected to maximize the amplitude of the undistorted output waveform. At this static current value, the output sine wave cuts the peaks at both the upper and lower sides.

maychang

Only when the collector current is determined first, will the top or bottom be cut first due to inappropriate selection of the collector load resistance.