Or not charge at all😊The issue is charging a given cap to a given voltage. If you charge the cap to a lower voltage than the source, the PERCENT loss is HIGHER
Thanks for the lecture, But at 15:58 you said increasing Re increases efficiency. I did not get that. As per your efficiency equation, Re in the denominator and increasing Re must decrease the eff right?
Thanks for the lecture. I have a question. At 4:11, at the second state, how do you define Vc1? how do you know Vc1 is still VDD? (Did you assume C1 is very large so small ripple approximation applies?) BTW: The switched capacitor converter looks so peculiar!
There is always resistance in the loop. Theoretically, if the resistance is zero, the current will be infinitely large and the circuit will emit an electromagnetic wave.
@@sambenyaakov Infinite current in ideal circuit is no problem. There are no parasitic resistances, no inductances, so no electromagnetic emmision (I think). So, there must be explanation where that energy goes (law of conservation of energy must apply)
Very nice video, thank you professor!
👍🙏
Thanks for sharing. In summary, sometimes one can think of not fully charge a Cap to obtain smaller charge sharing loss and switching loss.
Or not charge at all😊The issue is charging a given cap to a given voltage. If you charge the cap to a lower voltage than the source, the PERCENT loss is HIGHER
Thanks for the lecture, But at 15:58 you said increasing Re increases efficiency. I did not get that. As per your efficiency equation, Re in the denominator and increasing Re must decrease the eff right?
That is not what it is said. Increasing Re will change gain "AT THE EXPENSE OF EFFICIENCY"
@@sambenyaakov thanks professor. I misheard expense as expand.
Thanks Sam Ben-Yaakov. One question for you. How would you calculate the RMS current for a switched capacitor converter?
See
www.ee.bgu.ac.il/~pel/pdf-files/jour136.pdf
and the referenced papers
Thanks for the lecture. I have a question. At 4:11, at the second state, how do you define Vc1? how do you know Vc1 is still VDD? (Did you assume C1 is very large so small ripple approximation applies?)
BTW: The switched capacitor converter looks so peculiar!
Yes this is for the ideal case.
I would appreciate a lot if you could share the references that show the derivation of Re at 13:00. I tried by myself but failed...
See
www.ee.bgu.ac.il/~pel/pdf-files/jour136.pdf
www.ee.bgu.ac.il/~pel/pdf-files/conf147.pdf
www.ee.bgu.ac.il/~pel/pdf-files/jour131.pdf
Page 7. Assume we have ideal capacitors (zero ESR). Where will the energy (delta E) go?
There is always resistance in the loop. Theoretically, if the resistance is zero, the current will be infinitely large and the circuit will emit an electromagnetic wave.
@@sambenyaakov Infinite current in ideal circuit is no problem. There are no parasitic resistances, no inductances, so no electromagnetic emmision (I think). So, there must be explanation where that energy goes (law of conservation of energy must apply)
A current impulse emits an electromagnetic wave which radiates the energy.
@@sambenyaakov Thank you for reply.