Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

damping factor in PLL....

Status
Not open for further replies.
Z

zhangjavier

Advanced Member level 4
Joined
Jan 10, 2005
Messages
102
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,296
Activity points
757
pll damping factor

Generally we set the damping facotr be be between 0.7 and 1, but sometimes larger damping factor, such as 3 or even larger are used. Can someone tell me how the damping factor infulence the PLL performance ? What 's the criteria to deciede the damping facotr?

Thanks ~
 

damping factor pll

system having damping factor greater than 1 is very difficult to analyse and also less tools are available to analyse it....so we should be cautious when we are using such systems
 

damping factor 0.7

If you have a PLL that has a wide range of divider ratios, you find that the damping factor changes as the divider N changes. For the smallest N (highest open loop gain), you set the damping to be the least that you can have, and then when N goes to its highest value, you live with the resulting overdamping. That way you at least have a stable PLL over the entire frequency range.
 

pll damping factor vs peaking

electronics_kumar said:
system having damping factor greater than 1 is very difficult to analyse and also less tools are available to analyse it....so we should be cautious when we are using such systems
Click to expand...

But there do exist PLLs with damping facotr larger thant 1...What's the benifit ?

Added after 24 minutes:

biff44 said:
If you have a PLL that has a wide range of divider ratios, you find that the damping factor changes as the divider N changes. For the smallest N (highest open loop gain), you set the damping to be the least that you can have, and then when N goes to its highest value, you live with the resulting overdamping. That way you at least have a stable PLL over the entire frequency range.
Click to expand...

So what is the exact benifit if damping facotr large than 1?
 

pll & damping factor

with greater damping factor, you get less jitter peaking.
 

damping factor greater than 0.7

i think the PLL with high damping factor are used in demodulation , and data recovery

but PLL with low damping factor are used in freq synth.


khouly
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top