Hey Folks,
First post and already a question. Sorry for the entrance.
I'm taking an Electronics Course and we are assigned to design a Common Emitter Amplifier. Now I searched the site but no question has the same property as mine. We aren't given a operating point, so no Q current.
I've attached the Basic Schematic that we are given and are supposed to work with.
The Question Asks,
We are to drive an 8 Ω speaker with a max of 5 Watts RMS. Choose the Quiescent state to optimize dynamic range. The Transistors beta is 100. Resistors are to be chosen to give an output impedance of 0.8Ω within 10%. The Caps are to give a rolloff at 10Hz.
Now while I started thinking and working on this, I figured that I should have a Quiescent Voltage of 0 V at the emitter. Thus I get 0.6 Volts at the base. I can figure out the ratio of R1 and R2 to be \(\frac{0.6-30}{-30-0.6}\). So if i choose R1 or R2 i can get a value for the other. Now what about Re though? Which way should I approach thinking about this?
Thanks for any help.
EDIT: The 2N222 should be a generic transistor and not the 2N222 specifically. I used this in a SPICE simulation
First post and already a question. Sorry for the entrance.
I'm taking an Electronics Course and we are assigned to design a Common Emitter Amplifier. Now I searched the site but no question has the same property as mine. We aren't given a operating point, so no Q current.
I've attached the Basic Schematic that we are given and are supposed to work with.
The Question Asks,
We are to drive an 8 Ω speaker with a max of 5 Watts RMS. Choose the Quiescent state to optimize dynamic range. The Transistors beta is 100. Resistors are to be chosen to give an output impedance of 0.8Ω within 10%. The Caps are to give a rolloff at 10Hz.
Now while I started thinking and working on this, I figured that I should have a Quiescent Voltage of 0 V at the emitter. Thus I get 0.6 Volts at the base. I can figure out the ratio of R1 and R2 to be \(\frac{0.6-30}{-30-0.6}\). So if i choose R1 or R2 i can get a value for the other. Now what about Re though? Which way should I approach thinking about this?
Thanks for any help.
EDIT: The 2N222 should be a generic transistor and not the 2N222 specifically. I used this in a SPICE simulation
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