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    how do transform the inductor (passive element) into transistor (CMOS) based

    hi, everyone.

    I am new in designing a band pass filter with LC circuit. Now i would like to transform the LC lumped element circuit into the CMOS-based transistor circuit. What is the method that suitable for me to convert the LC circuit into CMOS transistor circuit? Is it any calculation required?

    The image i attached in below is my filter circuit in LC lumped elements, hope you guys can refer.
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    Re: how do transform the inductor (passive element) into transistor (CMOS) based

    This filter cannot be transformed onto CMOS equivalent, it's too complicated.( it has many drawbacks in term of layout and you can almost never obtain a good result due to complicated structures and couplings ). Instead, you should consider "Distributed Type Filters".


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    Re: how do transform the inductor (passive element) into transistor (CMOS) based

    Is it impossible for me to build UWB bandpass filter in transistor form? (ignore the lumped element circuit)



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    Re: how do transform the inductor (passive element) into transistor (CMOS) based

    It's apparently an elliptic filter with wide pass band and steep transitions, apart from the question if it's a reasonable LC implementation, an active filter will better use separate high and low pass functions. Instead of "transforming" the LC circuit, you'll design a suitable active filter topology. Not sure if the sharp characteristic can be implemented in silicon, particularly considering tolerances and parameter drift.


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    Re: how do transform the inductor (passive element) into transistor (CMOS) based

    Quote Originally Posted by xinhui View Post
    Is it impossible for me to build UWB bandpass filter in transistor form? (ignore the lumped element circuit)
    What does it mean "transistor form " ?? Did you mean "Active Filter" ??
    I don't think that this filter who works at 3.8GHz can be realized as Active Filter.In fact, there are some academical works on the subject but they don't seem feasible and consistent.
    If the substrate has high di-electric coefficient , this filter can be realized with distributed elements.It will occupy lesser area, more reliable.



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