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Simulators >> Circuit Simulators >> ppm detector
https://designers-guide.org/forum/YaBB.pl?num=1278905634

Message started by casual on Jul 11^th, 2010, 8:33pm

Title: ppm detector
Post by casual on Jul 11^th, 2010, 8:33pm

I got a phase loop for random data running at 5GHz 200ps. Because the BW is only around 4MHz, the ppm detector got to be around 0.2ps resolution or +/-800ppm. (correct me if i am wrong).

the structure is 5GHz clk following by a divider32(156.25MHz or 6.4ns) and then a counter with N bits. The 156.25MHz is used due to the clkref in the freq loop.

To achieve the resolution -->200ps/2048 = 0.1ps (500ppm)

The one cycle of ppm detector will be 6.4ns x 2048=13.1us!!

How could I simulate this in spectre?
Unless i use higher freq clk to the counter.

Is the above statement correct??

Title: Re: ppm detector
Post by ywguo on Jul 14^th, 2010, 7:05pm

Hi Casual,

I don't understand what your circuitry is going to do. What does ppm mean in your scenario?

By the way, I think your question should be posted in design section, like mixed signal design or high speed communication.

Yawei

Title: Re: ppm detector
Post by casual on Jul 27^th, 2010, 12:29am

It is a freq detector that have capability to set ppm (part per million) of a freq. I posted in the analog forum but moderators shifted it to here.