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Design >> Analog Design >> 3.3V analog PLL vs 1.2V analog PLL
https://designers-guide.org/forum/YaBB.pl?num=1159295356

Message started by ccd on Sep 26^th, 2006, 11:29am

Title: 3.3V analog PLL vs 1.2V analog PLL
Post by ccd on Sep 26^th, 2006, 11:29am

I have a 3.3V analog PLL now and am thinking about replacing it with a low voltage PLL to reduce area. However, I can think of a lot of potential design issues associated with low voltage PLL, such as higher clock jitter because of higher VCO gain, lower headroom for the chargepump circuit, potential gate leakage on the filter caps due to thinner gate ox, and so on. There seems more cons than pros that discourage me from pursuing going with a low voltage PLL. Basically, I have to deal with more design issues and give up some jitter performance for smaller area.

Title: Re: 3.3V analog PLL vs 1.2V analog PLL
Post by ACWWong on Sep 26^th, 2006, 12:13pm

yes, if it not broken, no need to fix it.
The main advantage should be reduction in power consumption and if you are going to a modern deep-submicron process you'd be better up facing the issues and over coming them then trying to migrate an old design with bolted on fixes (regulators/ Vboost etc.)