Search:

Type: Posts; User: frankrose

Page 1 of 20 1 2 3 4

Search: Search took 0.04 seconds.

  1. Replies
    3
    Views
    619

    Closed: Re: Applications I can work On

    4) motorized toilet brush. It would be more effective I guess.
    5) motorized curtain. Not interesting, just practical.
    6) motorized door closer. Nobody has to lie anymore that it was done.
    7)...
  2. Closed: Re: How Device Resistance change with respect to W and L in any technoogy

    On you figure the sheet resistance is 330 Ohm, you set 2kOhm for the desired value with 2um desired width. Cadence will calculate the necessary length from these parameters by a function like this:
    ...
  3. Closed: Re: Why is pmos and nmos put vertically and not side by side(horizontally)in ic layou

    planar IC fabrication is "side by side", vertical MOS channels are not existing or at least not conventional, I have never saw it. Or what do you mean under they are put vertically?
    Go through a...
  4. Replies
    18
    Views
    593

    Closed: Re: NMOS LDO current sense circuit help

    I think you could try these things:
    a, add calibration to balance the error of the current mirror. It is reliable, many ways you can implement it, some example:
    - analog: potentiometer instead of...
  5. Replies
    18
    Views
    593

    Closed: Re: NMOS LDO current sense circuit help

    I think you have too much gain in the current control loop, and if the speed of the control loop is comparable with the settling speed of the main LDO feedback system, than it can cause unstability...
  6. Closed: Re: Different connections to Common node in differential pair

    yes, scenario 3, sorry for the typo.
    I think it is reasonable when VDD is about a Vgs+Vdsat=Vth+2×Vdsat. This is the minimum VDD for an active current-mirror loaded quasi-differential pair.
    Vth...
  7. Closed: Re: Different connections to Common node in differential pair

    1. use to improve linearity. it is an easy way, low cost, and possible to implement degeneration without high common mode reduction if you use 2 tail current sources for Q1 and Q2, and the...
  8. Closed: Re: How to build a oscillator by using a Sallen Key filter.

    Just an other way to get sine wave is to add low-pass filter stages to the output to remove harmonics from the distorted signal.
  9. Replies
    1
    Views
    215

    Closed: Re: TSMC 65nm mocap_rf varactor

    Everything should be described in the PDK (Process Design Kit) documents, don't you have those .pdf files? Place one in your schematic and check its properties (press Q), maybe it is described there.
  10. Closed: Re: How to build current source based on modified Hawland current pump for 150 mA?

    By the equation from you (I didn't check) if you set R5=R4-R2 it should handle the load dependence.
    I think your input source at Vin has a varying internal resistance maybe. How you generate Vin?
  11. Closed: Re: CMRR is less than the DC differential gain

    2 possible reasons:
    a, you have big common mode gain because CMRR(dB) = Ad(dB) - Acm(dB)
    b, you do something wrong
    Check signs, expressions in calculator, the testbench itself.
  12. Replies
    1
    Views
    157

    [SOLVED]Closed: Re: Mismatch Contribution Analysis

    Look for Monte Carlo analysis in google:
    https://miscircuitos.com/monte-carlo-simulation-cadence-virtuoso/
  13. Replies
    3
    Views
    289

    Closed: Re: Op-amp and compensation

    One point of Miller compensation is to transform a smaller capacitance to a bigger value and it will appear on the highest resistive value node, which is the OTA's output. It determines the dominat...
  14. Closed: Re: Impact of load resistor on transistor audio amplifier

    In general, 3 diodes to bias class-AB common-drain stage is not too good idea I think. In post #1 the transistors dissipate more than 9W in idle state. Be cautious. They wil burn.

    To maximise the...
  15. Closed: Re: How to find dynamic charactersitics of an ADC?

    It is foggy what is your problem with cadence. Where did you stuck?
    Software error/warning issue?
    Or analysis setup is not clear?
    Or how to create the testbench?
    Using postprocess, calculator...
  16. Replies
    3
    Views
    561

    Closed: Re: Matching of big array transistors

    E is dummy device?

    I am not sure, but drain and source connections shouldn't matter too much, rather the bulk of the transistors.
    Group same NMOS (A,B) and same PMOS (C,D) transistor pairs, like...
  17. [SOLVED]Closed: Re: Feedback SMPS; Transfer function for error amplifier with series RC to GND connec

    If the potential, or voltage between the 3 resistors is phi1, these equations are true:
    a. Vin/Rin = I_R1
    b. I_R1 = phi1/R3 + (phi1 - Vopamp)/R2
    c. I_R1 = -phi1/R1

    From c.: phi1 = -I_R1 * R1...
  18. [SOLVED]Closed: Re: Feedback SMPS; Transfer function for error amplifier with series RC to GND connec

    An inverting amplifier (which is also an error amplifier, with ground reference) has a transfer function: H(s)=-Rf/Rin, where Rf is the feedback resistor, and H(s) is independent from s, the complex...
  19. Replies
    11
    Views
    1,302

    Closed: Re: Help for my Collpits oscillator circuit

    I disagree. If the open-loop gain is smaller than 0dB of the oscillator with the 50 Ohm load it simply won't give any signal. I mean if gain less than 0dB at the resonance frequency.
  20. [SOLVED]Closed: Re: Feedback SMPS; Transfer function for error amplifier with series RC to GND connec

    Yes, there is a difference, because amplifier has different relationship between its terminals. But as I see in google at the SMPS it is not a case, lot of paper calls above compensator circuit as...
  21. Closed: Re: Source degeneration for differential amplifier

    Increasing of L doesn't help on linearity, you just move operating point to less steeper point of the square law characteristic. However degeneration uses the high non-linear gain of the diff.pair to...
  22. Replies
    11
    Views
    1,302

    Closed: Re: Help for my Collpits oscillator circuit

    Hi,
    Spectrum analysers have 50 Ohm input impedance. Your simulations didn't contain it I think. Probably the measurement device overloaded your circuit and of course other mentioned reasons above...
  23. [SOLVED]Closed: Re: Feedback SMPS; Transfer function for error amplifier with series RC to GND connec

    figure 1 hasn't got resistive feedback to ensure the operating point. do you want an integrator or an amplifier here? because it is not an amplifier.
    figure 2 has positive feedback, inverting input...
  24. Replies
    4
    Views
    946

    Closed: Re: Opamp Design Procedure,

    There is no silly question, just be more accurate please. If you are familiar with stuffs what is this headache with the drain-source voltage? In general a simple diode-connected device force the...
  25. Closed: Re: How to verify MOSFET resistance implemented as a nulling resistor in an OpAmp

    Hi,
    In DC analysis you can plot with calculator the ON resistance easily, just tick the "save operating points" at the analysis window, and use this expression: OP("/Mz", "ron")
Results 1 to 25 of 500
Page 1 of 20 1 2 3 4