You may read some theory here:
Common Emitter Amplifier and Transistor Amplifiers
welcom Shayaan_Mustafa
as I know you can't design amplifier without knowing some values like\[ R_E \]and\[ R_C\] and\[ \beta\] .
when you have sufficient elements to design you can start.
designing relations -which is true and used in design- are:
\[
I_{CQ}=\frac{V_{CC}}{R_{ac}+R_{dc}}
\]
\[
R_B=0.1 * \beta * R_E
\]
\[
R_1=\frac{R_B}{1-\frac{v_{BB}}{v_{CC}}}
\]
\[
R_2=\frac{R_B V_{CC}}{V_{BB}}
\]
at most time design is to find the value of\[ R_1\] and\[ R_2 \]which can select the type of work area and the Q-point which is the goal in ac and dc for prober using of amplifier .
i hope this help .
best regards .
Hello Shayaan_Mustafa,
I think - before starting to calculate some values based on given formulas - as the first step you should try to understand the meaning and the task of each part of the circuit.
What is the task of Re and why is there a capacitor Ce? Only then you really can understand the content of the formulas - and the region in which you can/must select the values.
Thanks for reply
What is Rac and Rdc?
We can calculate RE from
RE=\[\frac{VRE }{IE }\]
We can also calculate β from
β=\[\frac{IC }{IB }\]
RE is to easily ground signals.
What means "easily"? Wouldn't it be easier without any resistor? Did you hear already about feedback?
CE is a bypass capacitors which ground AC signals of high frequenc
Why? What is the goal to be achieved?
welcome
Rac and Rdc is the equivalent resistance in emitter-collector circuit in dc/ac . for example for common emitter configuration
\[R_{ac}=R_E + R_C || R_L . \]
\[R_{dc}=R_E + R_C .\]
if we consider that \[R_E\] is not bypassed by a capacitor and the load \[R_L\] is connected through capacitor .
capacitor is open circuit in dc because \[ X_C = \frac{1}{j2 \pi f c} \] and f=0(ideal) in dc and varies in ac .
and \[\beta\] can by known from the datasheet of amplifier .
RE provides dc feedback (independent on CE) - thereby stabilizing the operating point.
No, the opposite is true. Without CE you also will have signal feedback - thereby reducing distortions.
______________
Perhaps now you understand my recommendation regarding understanding the purpose and the effect of each part.
Mustafa, sorry but nothing is correct.
You really should try first to learn some BJT amplifier basics. There are a lot of sources (books, articles) that can be found in the internet.
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