Extracting information from a Bode Plot (PM, GM, etc...)

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The discussion focuses on extracting key parameters from a Bode plot for a unity feedback system, including DC Gain, Bandwidth, Gain Bandwidth Product (GBW), Phase Margin, and Gain Margin. The user confirms the calculation of DC Gain as 10,000 based on the provided formula. For bandwidth, it is noted that the loop gain for a unity feedback system is the same as the open-loop gain of the amplifier, with bandwidth typically defined as the 3dB-Bandwidth. Stability margins can be derived using standard definitions, and the user seeks guidance on these concepts due to a lack of resources. The conversation emphasizes the importance of understanding these definitions for effective analysis.
Waxterzz
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Hi all,

1. Homework Statement

http://imgur.com/kqZK1Vv

This is the loop gain (A.F.) of unity feedback system.

I need to extract

DC Gain
Bandwidth
GBW (is GBW Gain Bandwith ?)
f unity (I suppose this is unity frequency)
Phase Margin
Gain Margin

What is the optimal PM and f2/GBW for time and frequency domain applications?

Homework Equations


Don't know => this is not really homework as such, plus in the books I got about electrical engineering not much is said about stability and feedback...

The Attempt at a Solution



U guys don't need to solve this for me,

What I want is instructions how I can solve it, since I truly have no material about this topic, then I shall try and present it, and you guys can help me furtherKind Regards.
 
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DC Gain =>

80 = 20 log | DCGain |

So DC Gain = 10^4 = 10000

Is this correct?
 
Waxterzz said:
DC Gain =>

80 = 20 log | DCGain |

So DC Gain = 10^4 = 10000

Is this correct?
Yes.
Next: bandwidth?
 
Loop gain for a unity feedback system is identical to the open-loop gain of the amplifier.
Hence, you have nothing to do than to apply the definitions of the various data you are interested in.
Normally, the "bandwidth" is identical to the 3dB-Bandwidth.
Stability margins can easily derived by using the appropriate definitions.

Do you know all the definitions?
 

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