Question about realizing constant gm opamp

[xz781122]

d. flandre gm/id methodology

in many papers if you want to design constant gm op-amp you must realize sqrt(Iq)+sqrt(In)=constant.but their design seems to make Iq+In=constant.why?

 

[nxing]

about cnstant gm opamp

please go to more details, like which paper or give the schematic...

 

[watersky]

about cnstant gm opamp

the input is nmos and pmos,tail current is two pieces of 1:3.you can find papers about it.

 

[markty]

about cnstant gm opamp

What do u mean by making Iq + In = constant?
Is it Ip + In?
I read some papers before, i rememberd that some voltage is constant. For current, it is always constant.

 

[chaitu2k]

Re: about cnstant gm opamp

u may want to take a look at this

F. Silveira, D. Flandre, P. Jespers, "A gm/ID Based Methodology for the Design of CMOS Analog Circuits and its Application to the Synthesis of a Silicon-on-Insulator Micropower OTA", accepted for publication in the IEEE Journal of Solid-State Circuits.

 

[sunking]

about cnstant gm opamp

You can refer to the papaer about "rail to rail".
Those paper in the board you can find many.

 

[kkoko]

Re: about cnstant gm opamp

because Bn+Bp also is constant