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How to increase the bandwidth on this topology?

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demodb

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bandwidth LNA

hello guys, anybody got any idea how to increase the bandwidth on this topology. I think its limit is determined by Rd and the output capacitance (which isn't seen in the picture but is 1p [F]).
I want to use this topology for a DECT system, so its bandwidth needs to be 1.9G [Hz]. But with the gain i want i can't reach the wanted bandwidth. Anyone any ideas? I know one thing is to replace Rd by a coil, but are there any other solutions. Coils are not really wanted in IC design.
 

Re: bandwidth LNA

if you replace Rd with an inductor your bandwidth may become even worse, because the inductor itself in combination with the parasitics at the drain has bandpass characteristics. on the other hand your input match won't be broadband either, as you use Lg and Ls to match the input and these inductors match the transistor in a narrowband. to overcome this, you may use common-gate topology and continue to use Rd (unfortunately lower voltage headroom) and avoid to increase the capacitance at your drain node with careful transistor dimensioning and layout generation. as you see these are all trade-offs and there is never an optimum solution.
 

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