Class A amplifiers formulae help

AI Thread Summary
A user seeks assistance with calculations related to a single-stage Class A amplifier, providing specific parameters such as Vcc, Vceq, Icq, RL, and Ip. They have successfully identified formulas for DC Input Power and overall efficiency but are uncertain about the calculations for DC Power Loss in the load resistor, AC power developed across the load resistor, DC power delivered to the transistor, and DC power wasted in the transistor. The discussion highlights the need for a schematic to accurately calculate these values, as biasing methods can affect total harmonic distortion and quiescent power dissipation. Additionally, the concept of "wasted" power in the transistor is noted to be ambiguous, as it varies with input signals. The user is encouraged to clarify their understanding and seek confirmed formulas for their calculations.
shaiqbashir
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HI guys!

well! i have got a question with me. Some forumlae i know and some i dont! please help me in solving it.

There is a single stage class A amplifier which has

Vcc =20V
Vceq = 10V
Icq = 600 mA
RL = 16ohms
Ip=300mA.

We have to find:

1) DC Input Power
2) DC Power Loss in load resistor
3) AC power developed across load resistor
4) DC power delivered to the transistor
5) DC power wasted in transistor
6) OVerall efficiency

okz, now i know how to find (1) and (6). What should i do for remaining. Following I am wrtitng what i think about them. Please tell me if I am wrong or correct. If I am wrong then what is the correct formula:

2) P = (Icq^2) RL
3) P=0.5 Icq x Vceq
4) don't know
5) don't know

Please tell me those formulae which i don't know and also make those confirmed which i have written above.

i shall be thankful to u for this act of kindness.

Good Bye!
 
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Do you have a schematic of this amplifier? You can bias up class A amps in different ways to trade off THD versus quiescent power dissipation. Without more info, I don't think you can calculate several of the quantities you are asking for.
 
Well! for the 1st question, i don't have a schematic. i have written that as it came to me. It is just written that it is a single stage class A amplifier. So please be straight forward.
 
shaiqbashir said:
5) DC power wasted in transistor
I remember this as being thought of as the power consumed with no input signal supplied.
This is not a clear concept due to the fact that "wasted" and "efficiency" vary with the input signal.
 

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