How Does Q Factor Influence Gain in a Parallel LC Circuit?

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SUMMARY

The Q factor significantly influences gain in a parallel LC circuit, where a higher Q results in greater gain at the resonant frequency. To achieve a higher Q, one must decrease inductance and increase capacitance. For example, a configuration with 10,000 microfarads and 1 microhenry will yield more gain than one with 1,000 microfarads and 1,000 microhenries. However, increasing the Q factor also reduces bandwidth, necessitating a balance based on amplification needs.

PREREQUISITES
  • Understanding of parallel LC circuits
  • Knowledge of Q factor and its mathematical representation
  • Familiarity with impedance concepts in electrical circuits
  • Basic principles of resonance in RLC circuits
NEXT STEPS
  • Study the mathematical derivation of the Q factor in RLC circuits
  • Explore the impact of resistance on Q factor and circuit performance
  • Research methods to minimize losses in LC circuits
  • Investigate the trade-offs between Q factor, gain, and bandwidth
USEFUL FOR

Electrical engineers, circuit designers, and students studying resonance and amplification in RLC circuits will benefit from this discussion.

Idea04
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I would like to know somethings about the Q and its relation to gain in a parallel LC circuit.
From what I know by tuning the Q to be high you can get a lot of gain at resonant frequency. Also to tune for Q the inductance has to be decreased and the capacitance has to be increased. Is this right? If so then for a matter of speaking, if you had a capacitance of 10000 microF and 1 microH for a resonant frequency would there be more gain than 1000 microF and 1000 microH for a resonant frequency. I think that the lower the impedance in the circuit the higher the gain will be. can someone clarify this.
 
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You may want to go to Wikipedia and look up "Q factor" and "RLC circuit".

To increase the Q factor you minumize the losses due to resistance. You don't always want to maximize the Q. The bandwidth decreases with increased Q. It all depends on what you want to amplify.

For an LC circuit with resistance (RLC) wikipedia gives the Q as:

Q=\frac{1}{R}\sqrt{\frac{L}{C}}
 
Most likely this can only be answered by an "old timer". I am making measurements on an uA709 op amp (metal can). I would like to calculate the frequency rolloff curves (I can measure them). I assume the compensation is via the miller effect. To do the calculations I would need to know the gain of the transistors and the effective resistance seen at the compensation terminals, not including the values I put there. Anyone know those values?

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