please dont rip this site

Interactive Digital Phase Locked Loop Design


This is an interactive design package for designing digital (i.e. software) phase locked loops (PLLs). Fill in the form and press the ``Submit'' button, and a PLL will be designed for you.

I've been advised to say that, although I believe the package to be bug-free, you use the results at your own peril, and you're advised to check them for correctness before using them. Don't blame me if your aircraft falls out of the sky!

The Java code generated by this package is the way it is for pedagogic reasons, and could easily be ``tightened up''.

The graphs are produced with the help of the excellent gd GIF manipulation library, originally from Quest Protein Database Center.

Here are some references to textbooks which will tell you about analogue and digital PLLs, and here is a short glossary of technical terms.

A companion page generates digital filters.

An email message, saying what you like and don't like about this package, will be appreciated.

Fixed fields:

One day, you might be able to alter these values.

Parameter Value
Order of loop 2
Input Complex z
Output Real phase phi
Phase detector dphi = Im { z e-j phi }
Loop filter Proportional-Integral

Fill in all of the following:

Parameter Symbol Units Value
Sample rate fs sample/sec
Centre frequency f0 Hz

Select two of the following:

You must select one A button and one B button. The following combinations are legal:

  A B
Combination 1: zeta any other parameter
Combination 2: tau1 tau2

A B Parameter Symbol Units Values
Damping factor zeta     A:  
Integrator time constant tau1 sec
  Other time constant tau2 sec
  Natural frequency fn Hz
  Noise bandwidth BL Hz

Optional fields:

None at the moment.

That's it!   Press ``Submit'':

Submit form:     Reset form:

Tony Fisher /

See also:

file: /Techref/uk/ac/york/cs/www-users/http/~fisher/mkpll/index.htm, 4KB, , updated: 2011/8/22 16:27, local time: 2017/1/17 22:30,

 ©2017 These pages are served without commercial sponsorship. (No popup ads, etc...).Bandwidth abuse increases hosting cost forcing sponsorship or shutdown. This server aggressively defends against automated copying for any reason including offline viewing, duplication, etc... Please respect this requirement and DO NOT RIP THIS SITE. Questions?
Please DO link to this page! Digg it! / MAKE! / 

<A HREF=""> Interactive Digital Phase Locked Loop Design </A>

After you find an appropriate page, you are invited to your to this massmind site! (posts will be visible only to you before review) Just type in the box and press the Post button. (HTML welcomed, but not the <A tag: Instead, use the link box to link to another page. A tutorial is available Members can login to post directly, become page editors, and be credited for their posts.

Link? Put it here: 
if you want a response, please enter your email address: 
Attn spammers: All posts are reviewed before being made visible to anyone other than the poster.
Did you find what you needed?

  PICList 2017 contributors:
o List host: MIT, Site host, Top posters @20170117 Van Horn, David, David Duffy (AVD), RussellMc, IVP, Justin Richards, Sean Breheny, alan.b.pearce, speff, Brent Brown, Neil,
* Page Editors: James Newton, David Cary, and YOU!
* Roman Black of Black Robotics donates from sales of Linistep stepper controller kits.
* Ashley Roll of Digital Nemesis donates from sales of RCL-1 RS232 to TTL converters.
* Monthly Subscribers: Gregg Rew. on-going support is MOST appreciated!
* Contributors: Richard Seriani, Sr.

Welcome to!