Common Emitter amplifier that amplifies a signal by gain of A_v while applying a phase shift of 180 degrees to the signal. This amplifier is to be connected to a circuit driving a speaker.
Emitter current is biased at 2.5mA w/ R_e resistor for improved current stability over beta and temperature variations.
Tune potentiometer to vary A_v (gain). Close and re-run transient plot each time potentiometer is changed so that measured signals are re-centred at 0V DC.
In this setup, maximum output range occurs when A_v <= 2.28 (R_pot <= 779ohm). This means input signal can have an amplitude as large as 850mV without distorting (in theory).
Specs:
-> Max gain on Amplifier (to keep BJT in active mode): A_v = 4.57 (R_pot = 1.56kohm)
- The max gain you can apply to your input
signal without distorting it will now depend
on the amplitude of the input signal itself.
-> Range of input signal (w/o distorting signal):
- This depends on what you set the gain to.
- The following calculations will tell you the
max amplitude your input signal can be
based on what you set A_v (technically
R_pot) to.
Calculations:
-> A_v = 0.0029278*R_pot [V/V]
-> Input Ampl. < (3.875 - (2.5mA)(R_pot)) / A_v
OR
Input Ampl. <= 850mV
Use whichever is smaller.
