Search:

Type: Posts; User: shanmei

Page 1 of 17 1 2 3 4

Search: Search took 0.03 seconds.

  1. Replies
    15
    Views
    753

    Closed: Re: input current of the integrator

    Sure, the feedback loop of force negative and positive node of the opamp to be equal.

    Input current charges the negative node of the opamp, making it has a voltage rise, then the feedback loop...
  2. Replies
    15
    Views
    753

    Closed: Re: input current of the integrator

    Thank you for all your feedback.


    Why node Vx ( negative input node of the integator) does not change when the current charges Vx node, because it is is a low impedance node?

    For an...
  3. Replies
    15
    Views
    753

    Closed: Re: input current of the integrator

    Sorry I still do not understand.

    Assume the input current is dc current, it can not go through the feedback capacitor as I1, and it can not go into the negative input node of the opamp ( the gate...
  4. Replies
    15
    Views
    753

    Closed: Re: input current of the integrator

    Thank you for the feedback. Sure, a reset switch is needed to prevent saturation.

    But during the integration process, how can the current "goes through" the feedback capacitor? For example, if we...
  5. Replies
    15
    Views
    753

    Closed: input current of the integrator

    An integrator is built with an opamp and a feedback capacitor acossing the output node and negative input node of the opamp. The input current charges the negative input node, and the negative input...
  6. Replies
    1
    Views
    276

    Closed: sfdr simulation in Matlab

    I have a sine signal V1 with frequency 49.9MHz, and the sampling clock f1 with frequency is 110.6MHz. In Matlab, using sfdr(V1, f1), it brings the result as shown in Fig. 1. The fundamental signal is...
  7. Replies
    6
    Views
    450

    Closed: Energy harvest circuit questions

    153913

    I have several questions about energy harvest circuit as shown in the above figure.

    1. How is the " radiation signal" in the air converts to the voltage or current signal along the...
  8. Replies
    2
    Views
    250

    Closed: transformer S11 simulation

    I am building the transformer by using two inductors coupled with each other. Each inductor is a squred shape matal, and the two indcutors interweaving with each other.


    In ADS simulation, the...
  9. Replies
    10
    Views
    550

    Closed: Re: cadence to ADS EM simulation

    Thank you for all you reply. Yes, then I switched to the ADS EM simulation. It works for the coupling effect simulation.

    It is weird that Cadence dose not provide good RF simulation enviroment.
  10. Replies
    10
    Views
    550

    Closed: Re: cadence to ADS EM simulation

    Thank you for your reply.

    In Cadence, I want to simulate the two inductors placing very close. I don't know whether Cadence can simulate the coupling effect of the two inductors.


    If...
  11. Replies
    10
    Views
    550

    Closed: cadence to ADS EM simulation

    I have an inductor from cadence simulation. Can I export the S parameter from cadence and do the EM simulation in ADS? Thanks.
  12. Closed: Re: source pull simulation and input impedance match

    Thank you for your reply. [ATTACH=CONFIG]153282


    The Zo in the red cycle is always there, and the blank space after it is not for entering the Zo. It is for the Zs or ZL input.

    You can see...
  13. Closed: source pull simulation and input impedance match

    Design one stage power ampifier. After doing the load pull and source pull simulation, I got the load and source impedance. Then I do the impedance matching for both the input and output of the...
  14. Replies
    6
    Views
    1,036

    Closed: Re: A zero at folded cascode apmlifier

    Wz is a zero location.

    I didn't know what the zero location calculation can also use the gain-bandwidth constant relationship to obtain. Thanks.
  15. Replies
    6
    Views
    1,036

    Closed: Re: A zero at folded cascode apmlifier

    That's really helpful. Could you please explanate the zero? Why there is a zero and why the zero location is that? Thank you.
  16. Replies
    1
    Views
    626

    Closed: IC package company QFP80

    Is there any company can sell package QFP80? I never find it online. Thank you.
  17. Replies
    2
    Views
    1,178

    Closed: metal fill on the core circuit

    My chip is low frequency operation under 1MHz clock. For the layout, if the automatically metal fills on my core chip, whether it would influence the chip performance?

    Usually I select the option...
  18. Replies
    6
    Views
    1,036

    Closed: A zero at folded cascode apmlifier

    Why there is a zero by counting the gain from the input to node2. Why the gain at high frequency is gm1/gm2? Thanks.


    153070


    page 10.
    ...
  19. Replies
    6
    Views
    1,702

    Closed: Re: Resonant frequency sensing sensor

    Thank you for your replies.

    The antenna is a senor that its resonant frequency would change in the range of 1GHz-5GHz. For example, if the environemnet pH value changes, the resonant frequency of...
  20. Replies
    6
    Views
    1,702

    Closed: Resonant frequency sensing sensor

    Can the resonant frequency of different antennas being detected by a low-cost and simple method? Any sensor or chip? No VNA. Thanks.
  21. Replies
    4
    Views
    577

    Closed: Re: Voltage reading is not constant from DAQ

    In the DAQ software setup, I set the terminal configuration to be " differential", then the measured signal is stable without the ripple.

    152598
  22. Replies
    4
    Views
    577

    Closed: Re: Voltage reading is not constant from DAQ

    Thanks you. When I connects it with the differential mode, when there is no ripple.
  23. Replies
    4
    Views
    577

    Closed: Voltage reading is not constant from DAQ

    I have the NI6259 and want to read an analog signal.

    I connect DC voltage 0.35V to the AI0 analog input pin of NI6259 through a BNC connector. The ground pin of the signal generator is connected...
  24. Replies
    1
    Views
    330

    Closed: LCC52 and LCC84 Eagle model

    Does anyone have the LCC52 and LCC84 model for the Eagle PCB layout? Thank you.
  25. Replies
    9
    Views
    1,480

    Closed: Re: UHF RFID Chip impedance with 50 ohm

    20-j*200 is already the series equivalent circuit, and its impedance z=sqrt(20^2+200^2)=201 ohms.

    -20dBm=0.01mW=0.00001

    V=sqrt(2*P*R)=sqrt(2*0.00001*201)=63mV.

    Should the V=sqrt(2*P*R) or...
Results 1 to 25 of 402
Page 1 of 17 1 2 3 4