Gain Boost (Regulated Cascode) for cascoded cs amplifier

[eric84940]

I'm wondering if the gain boosting circuit below will malfunction or not?

Compare to the normal gain boosting circuit, it seems that both have almost the same voltage gain.

I suppose that Vds1 in the fig. fluctuates more than the normal one, but does it have any other lethal disadvantage?

Thanks in advance!
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[eric84940]

I'm wondering if the gain boosting circuit below will malfunction or not?

Compare to the normal gain boosting circuit, it seems that both have almost the same voltage gain.

I suppose that Vds1 in the fig. fluctuates more than the normal one, but does it have any other lethal disadvantage?

Thanks in advance!
[moderator action: removed link to external file server]

 

[Dominik Przyborowski]

You are trying to force ground to be equal to Vin. It does not work until Vin is set to 0.
In simpler words, this circuit is not functional as gain boosted amplifier, rather as open loop two stage amplifier (comparator, comparing Vin with ground)

 

[KlausST]

Hi,

ar you sure you want the inverting input connected to GND?

What is the target: Voltage_gain or current_gain?

Klaus

 

[eric84940]

Hi,

ar you sure you want the inverting input connected to GND?

What is the target: Voltage_gain or current_gain?

Klaus

I'm targeting on the voltage gain.

The strange idea popped as I saw Fig. 9.26(a) in "Design of Analog CMOS Integrated Circuits, 2nd" by B.Razavi.

I am wondering if the transconductance of M1 I drew in #2 can also be boosted by A1 just like the reference book indicates? (Although it can't be called as typical "gain boost" now)

And will the circuit work? (Even if it's an open loop circuit)