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[PLL] What is free running clock

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maulin sheth

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Hello all,

Can anyone guide me,What is the Free Running Clock?
What is the use of Free Running Clock?

Thanks in Advance.
 

rca

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Free running clock means the pll does not try to lock on a reference clock.
 

rca

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Well google and Wikipedia is your friend, that is the based of the pll behavior you need to learn.
A pll try to follow a reference clock, and act on a VCO voltage control oscillator to follow this clock. Some dividers and multiplier are in the different paths to increased or decreased the clock frequency.
 

sun_ray

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A free running clock is just a clock from which other clock can also be derived.
 

atulaxc

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Free running clock is not part of any standard. This is just a way of showing the independence in phase relationship of a clock on a chip to other clocks. The PLL's on chip can used free running clocks as input to generate fixed output clocks. This link has details on PLL.
 

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