The Designer's Guide Community Forum
https://designers-guide.org/forum/YaBB.pl
Design >> Mixed-Signal Design >> phase of the gated ring oscillator
https://designers-guide.org/forum/YaBB.pl?num=1446574384

Message started by saralandry on Nov 3rd, 2015, 10:13am

Title: phase of the gated ring oscillator
Post by saralandry on Nov 3rd, 2015, 10:13am

Hi,

I attached the schematic of a gated ring oscillator and its timing and phase diagram.
Having had this figure I have two questions.

First of all, can anybody describe the phase behavior of the gated ring oscillator? How does the oscillator start oscillating from the initial phase at the rising edge of input data? In fact I am interested in how to force ring oscillator start oscillating from an initial phase like this?

My second question is that how can I plot the phase of the gated ring oscillator as a function of time in the Cadence as you can see in the figure?

Thanks

Title: Re: phase of the gated ring oscillator
Post by wandola on Nov 5th, 2015, 1:40am

GRO is very easy to understand. When u close the switch, the GRO becomes a ring oscillator. when u open the switch, the ring oscillator stops and the phase is hold;

the other one, Gated switched ring oscillator is really hard to understand. If u dig into the Korean guys's paper... :)

Title: Re: phase of the gated ring oscillator
Post by saralandry on Nov 7th, 2015, 8:21pm

Hi  wandola,

Tnx for the comment. Yes the concept is truly easy to understand. What I don't get is the starting point of  the phase from an initial value when the next enable signal comes. In the multipath gated ring oscillator proposed by Straayer, you can see the phase diagram and it keeps counting the phase instead of starting from the initial value.
I took a snapshot from the Korean guy's paper but it is actually GRO not GSRO.
Any Ideal ?

Title: Re: phase of the gated ring oscillator
Post by wandola on Nov 12th, 2015, 7:26pm

Hi,

Actually the phase should keep growing when the next start pulse comes.

However, the counter is a modulus operation. So the phase cannot grow infinite. It must go to 0 once it is saturated.

In the Korean guys paper, he makes it simple to follow. U can see the phase for next start pulse equals to the previous phase minus some x2*PI.  :D

The Designer's Guide Community Forum » Powered by YaBB 2.2.2!
YaBB © 2000-2008. All Rights Reserved.