wide band amplifiers + paper

[kahroba92]

hello freinds,

I am working on wideband amplifiers

during study this paper, i don't understand why it say "the changes in gm"

gm1,2 does not has any change? why not consider?

this is the paper: "A Wideband Analog-Controlled Variable-Gain
Amplifier With dB-Linear Characteristic
for High-Frequency Applications" (2016)

the shot of paper is here:

anyone can help me to understand?

tnx in advance!

 

[morfozar]

Hi,
by changing control voltage Vcn that applied to the gates of M4,M5 you can change its current Ids and respectively its gm