how to design a VCO with replica bias

[steadymind]

replica bias vco

Hi guys,

this is the first time I am designing a VCO. I need a differential ring osc. with replica bias.

how do i get the design started i know the freq. range but how to get the DC circuit conditions and the W/L of the transistors

 

[prashantbabu]

replica bias

Hi,
This paper will give you a good understanding of what you are looking for.

--Prashant

 

[neoflash]

vco replica biasing circuit

Hi,
This paper will give you a good understanding of what you are looking for.

--Prashant

Maneatis's design is beautiful but with a bunch of real problems.

I love it and hate it.

 

[steadymind]

bias replica

Hi Prashant,

Thanks for the paper. One small question... we know for oscillations to begin other than Barkhausen criterion a startup criterion is also required... Is there a relation for the Ring VCO.