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CMOS active inductor gyrator question

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promach

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How should I modify the gyrator circuit such that one of the inductor terminal is not connected to GND ?

http://tnt.etf.bg.ac.rs/~ms1aik/AIC-15-Active-Inductors.pdf#page=2

CMOS_active_inductor.png
 

Is it a serious question? The answer (one possible answer) is given on the next page of the linked lesson.

Floating L.PNG
 
The real gyrator circuitry CMOS implementation that I am dealing with is as follows:

Note I am using CMOS inverter as one of the transconductance block.

Now, with the page 3 example (floating inductor), I need to have "differential" version of my two following existing transconductance blocks.

CMOS_inverter_X1.png

Gm2.png
 

Asking how to modify an existing circuit is an almost different question.

You see that the straightforward approach in the linked paper utilizes a fully differential OTA. Considering possible alternatives, I think that the right side can be implemented also single-ended, with a single capacitor. gm1 can be implemented respectively as regular differential in - single ended out OTA. gm2 must be differential out, or can be replaced by two single ended OTAs, one with flipped inputs. CMFB is probably required.

In other words, you need at least OTAs with differential input. Your basic single stage OTA can be theoretically used, in practice you want additional current mirror folding for useful output swing.
 

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