As in section 2.2.3 of this phd thesis https://goo.gl/xJ8NgC , I have few questions:
3) How do we obtain expression (2.2) from (2.1) ?
As in section 2.2.3 of this phd thesis https://goo.gl/xJ8NgC , I have few questions:
1) Why assume "third order Butterworth frequency response with unity gain frequency" ?
As in section 2.2.3 of this phd thesis https://goo.gl/xJ8NgC , I have few questions:
4) How do we obtain the expression of open loop undamped natural frequency response, wno as (sqrt(2) * wc)?
because you are stabilizing an amplifier in the worst case scenario>> unity gain feedback at dc.
Quotebecause you are stabilizing an amplifier in the worst case scenario>> unity gain feedback at dc.
How is unity gain feedback at dc be the worst case scenario ? I do not get this
the opamp is in a unity-gain configuration which is the worst-case configuration for stability.
I recognize the Laplace transform there and finding the complex roots.
What year EE course does this Butterworth stuff ?
Do you know how to derive the transfer function for the single pole amplifier in negative feedback as in https://www.quora.com/Why-is-the-gain-bandwidth-product-of-an-amplifier-constant/answer/Aditya-Gaonkar-4 ?
I've been coming at this from the other end, learning about oscillators and looking for the least stable configuration, which is where gain and phase shift meet the Barkhausen stability criterion https://en.wikipedia.org/wiki/Barkhausen_stability_criterion of zero or 360 degree phase shift and unity gain. So unity gain at DC is approximating the ideal conditions for oscillation, obviously no phase to shift but fills the same criteria, if I understand it correctly which is not a given.
4) How do we obtain the expression of open loop undamped natural frequency response, wno as (sqrt(2) * wc)?
@Wimberleytech
Would you mind elaborating ?
For http://cc.ee.nchu.edu.tw/~aiclab/teaching/AIC/lect10.pdf#page=4 , why is the gain plot shifted down vertically ? Could anyone show some theory with respect to the open-loop transfer function H(s) ?
Besides, I recalled that reducing the gain-bandwidth product will also reduce power consumption in the case of two-stage opamp. Could anyone tell me how reducing feedback beta factor (B) could reduce power consumption from the perspective of internal circuitry of an opamp ?
For http://cc.ee.nchu.edu.tw/~aiclab/teaching/AIC/lect10.pdf#page=4 , why is the gain plot shifted down vertically ? Could anyone show some theory with respect to the open-loop transfer function H(s) ?
It is the A*Beta (or A*f, or in his case A*H(w) ) plot that is shifted down
QuoteIt is the A*Beta (or A*f, or in his case A*H(w) ) plot that is shifted down
Just to clarify the confusion probably for other readers, it is 20*log(beta*H(w)) instead of A*H(w) for the gain plot.
Why would the author plot beta*H(w) for gain ?
QuoteIt is the A*Beta (or A*f, or in his case A*H(w) ) plot that is shifted down
Just to clarify the confusion probably for other readers, it is 20*log(beta*H(w)) instead of A*H(w) for the gain plot.
Why would the author plot beta*H(w) for gain ?