Razavi Electronics2 Lec20: Examples of Capacitances in Bipolar Circuits, High-Freq. Model of MOSFETs

[@sahhaf1234]

Thank you very much.. These are not lectures but pure pleasure...

[@MuhammadAli-im9yl]

Before watching these lectures I was always reluctant to solve circuits involving frequency response. Very excellent way of building concepts from simpler to complex circuits.

[@coolwinder]

01:25 - Review of Lecture 19 06:54 - Bipolar Diff Pair - High-Frequency Circuit 13:55 - Bipolar Cascode Amplifier - High-Frequency Model 21:10 - High-Frequency Model of MOSFETs 29:15 - Example: CS Stage 31:35 - Example: CS Stage and P-Type Current Source Load 36:47 - Example; Source-Follower Stage with N-Type Current Source Load 42:38 - Example: CG Stage

[@Quran_memorization]

lec20 starts at 6:52

[@rachitjoshi23]

I am really happy to have you guys . No need for uni, schools, etc. Learn for free and have fun

[@alexnoggle1874]

I do wish there were more channels dedicated to electrical engineering concepts though. It feels very limited sometimes

[@CDexie]

@@alexnoggle1874 Guess the subjects are bit too specialized for casual entertainment. Watching a youtube video about how bridges are made can be mindless fun, I'm not sure if learning how FM works is

[@alexnoggle1874]

@@CDexie Yeah this definately isn't mindless fun lol. However there are still thousands of people who need to learn these complex topics every semester. There should be more lecture channels on microelectronics like this one.

[@Pulsonar]

@@CDexie Im not sure if any civil engineer would agree with how you said that "how bridges are made can be mindless fun, Im not sure if learning how FM works is" It comes across a bit disrespectful and ignorant of other disciplines that you dont know about. Besides, there are ways to make any academic topic "fun" theres no rule against that, it mostly depends on target audience, format and skill of the material, delivery and presenter.

[@rohithbhaskar976]

Great Lecture.... Thanks Sir :)

[@mnada72]

Waiting eagerly for circuit theory I & II and the rest of the series.

[@abdxlive]

33:00

[@coolwinder]

Professor, could you examine the case of PN diode and how is junction capacitance modeled as parallel capacitance, and also how does that capacitor act with different frequencies (as the frequency increases the voltage on that capacitor cant change as fast, that is, it follows the input terminal better (acts as lower resistance), or in the case second terminal was grounded, it would draw higher and higher current in order to change its voltage)? I think it could come nicely, so as to have better understanding about capacitances. Thank you immensely, your work will help drive innovation for decades to come! I hope you make more and more video lectures (I was writing to you asking for Electronics 2 video a couple of years back and I was surprised in the best way when I saw you have made it).

[@abdulazizalahmari1662]

DR, THANK YOU

[@coolwinder]

47:00 - Professor, when doing IC layout and routing bigger transistor matrices, inadvertently there will be made captive coupling between source and drain, does that mean we should by any cost try to lover it for cascode CG transistors, as to keep high-frequency characteristics?

[@coolwinder]

Professor, why don't we see capacitance between the collector and the emitter? I am asking as i have noted people saying that in IC, even if we separate transistors by putting them in different wells, what would form PNP junction, we still would have certain capacitance, or coupling across it; So why wouldn't we see the same in PNP transistor?

[@Quran_memorization]

38:36 as i learnt from razavi Cgs must go from gate to source but in this example, i think razavi did a wrong thing he connected CGS from gate to GND

[@Tikorous]

The source on that transistor is grounded so connecting that cap to ground is the same as connecting it to the source

[@Quran_memorization]

@@Tikorous oh i didnt notice that thank you very much bro

[@mrpossible5696]

Ty

[@muratt6894]

Thank You

[@therash09]

I don't understand how we can merge two capacitors connected to the same node on one side and to different grounds (one to absolute ground and the other to a.c. ground) on the other. Those two grounds can be at some non-zero potential with respect to each other, which means adding them directly might now be correct. Am I missing some basic thing here?

[@windee417]

It seems you have skipped Electronics 1. I advice you to follow that first.

[@therash09]

@@windee417 yes I skipped Electronics 1 due to paucity of time. I have planned to go through Electronics 1 later, but don't have time for it currently. If you could briefly address my doubt, I'll be very grateful to you. ☺️

[@windee417]

@@therash09 For small signal analysis we deactivate all independent sources. Current sources are opened and voltage sources are grounded. So for small signal model ac and dc ground are not different. Maybe I am not completely correct but this is what happening atleast until now from the beginning of Electronics 1.

[@hiteshsaini4260]

I have a doubt ie. In the last example Cgs and Csb1 should be neglected because while calculating the poles we Short circuit the input voltage source l.

[@razzakahmad8731]

thank you sir

[@xnxnxn0861]

why Vb set to GND?

[@黃彥銘-t4u]

Vb could be see as AC GND in small signal analysis