How commonly do you see PLL designs referred to as "type I", "type II", "type III", etc.? Do the terms make sense to you? I'm writing a report; don't want to either baffle with bullshit nor leave out handy terms... -- My liberal friends think I'm a conservative kook. My conservative friends think I'm a liberal kook. Why am I not happy that they have found common ground? Tim Wescott, Communications, Control, Circuits & Software http://www.wescottdesign.com
PLL Terminology Question
Started by ●October 11, 2012
Reply by ●October 11, 20122012-10-11
On Thu, 11 Oct 2012 15:36:55 -0500 Tim Wescott <tim@seemywebsite.com> wrote:> How commonly do you see PLL designs referred to as "type I", "type II", > "type III", etc.? Do the terms make sense to you? > > I'm writing a report; don't want to either baffle with bullshit nor leave > out handy terms... > > -- > My liberal friends think I'm a conservative kook. > My conservative friends think I'm a liberal kook. > Why am I not happy that they have found common ground? > > Tim Wescott, Communications, Control, Circuits & Software > http://www.wescottdesign.comIf I ran across those terms in a report I'd remember that somewhere years ago I'd seen them, but I'd certainly have to Google for what they actually meant. -- Rob Gaddi, Highland Technology -- www.highlandtechnology.com Email address domain is currently out of order. See above to fix.
Reply by ●October 11, 20122012-10-11
On Thursday, October 11, 2012 4:36:55 PM UTC-4, Tim Wescott wrote:> How commonly do you see PLL designs referred to as "type I", "type II", > > "type III", etc.? Do the terms make sense to you? > > > > I'm writing a report; don't want to either baffle with bullshit nor leave > > out handy terms... > > > > -- > > My liberal friends think I'm a conservative kook. > > My conservative friends think I'm a liberal kook. > > Why am I not happy that they have found common ground? > > > > Tim Wescott, Communications, Control, Circuits & Software > > http://www.wescottdesign.comTim, I don't generally see those terms and like Rob said, I'd have to look it up to be sure. Clay
Reply by ●October 11, 20122012-10-11
"Tim Wescott" <tim@seemywebsite.com> wrote:> How commonly do you see PLL designs referred to as "type I", "type II", > "type III", etc.? Do the terms make sense to you?IMO this terminology is used only in Gardner's book; there is no universal meaning. It is about P, PI, or PII control loop. Remnants of old times, when they used to mix the details of implementation with the type of the transfer function.> I'm writing a report; don't want to either baffle with bullshit nor leave > out handy terms...Since nobody is going to read it anyway, why would that matter? Vladimir Vassilevsky DSP and Mixed Signal Consultant www.abvolt.com
Reply by ●October 11, 20122012-10-11
On 11/10/2012 21:44, Rob Gaddi wrote:> On Thu, 11 Oct 2012 15:36:55 -0500 > Tim Wescott <tim@seemywebsite.com> wrote: > >> How commonly do you see PLL designs referred to as "type I", "type II", >> "type III", etc.? Do the terms make sense to you? >> >> I'm writing a report; don't want to either baffle with bullshit nor leave >> out handy terms... >> >> -- >> Tim Wescott, Communications, Control, Circuits & Software >> http://www.wescottdesign.com > > If I ran across those terms in a report I'd remember that somewhere > years ago I'd seen them, but I'd certainly have to Google for what > they actually meant.1+ -- Syd
Reply by ●October 11, 20122012-10-11
"Tim Wescott" <tim@seemywebsite.com> wrote in message news:zMudnS3Oobl6sOrNnZ2dnUVZ_q6dnZ2d@web-ster.com...> How commonly do you see PLL designs referred to as "type I", "type II", > "type III", etc.? Do the terms make sense to you? > > I'm writing a report; don't want to either baffle with bullshit nor leave > out handy terms... > > -- > My liberal friends think I'm a conservative kook. > My conservative friends think I'm a liberal kook. > Why am I not happy that they have found common ground? > > Tim Wescott, Communications, Control, Circuits & Software > http://www.wescottdesign.comI think it has to do with the type of phase detection used. You might look in a data book for a PLL chip. tm
Reply by ●October 11, 20122012-10-11
On Thu, 11 Oct 2012 15:58:33 -0500, Vladimir Vassilevsky wrote:> "Tim Wescott" <tim@seemywebsite.com> wrote: >> How commonly do you see PLL designs referred to as "type I", "type II", >> "type III", etc.? Do the terms make sense to you? > > IMO this terminology is used only in Gardner's book; there is no > universal meaning. > It is about P, PI, or PII control loop. Remnants of old times, when they > used to mix the details of implementation with the type of the transfer > function.It certainly has universal meaning in control systems terms: it's the number of integrating stages that are cascaded in the loop, either from the compensator or the plant. I had to sweat through it in my undergraduate days, then help undergrads sweat through it as a TA getting my Master's degree.>> I'm writing a report; don't want to either baffle with bullshit nor >> leave out handy terms... > > Since nobody is going to read it anyway, why would that matter?Pbpbpbpbpbtht. It will become a cult classic among my customer's customers, eagerly read and handed down from elder, competent and stately engineers to youngsters who are wet behind the ears and trying to make their systems match the performance of the existing ones in the field. -- My liberal friends think I'm a conservative kook. My conservative friends think I'm a liberal kook. Why am I not happy that they have found common ground? Tim Wescott, Communications, Control, Circuits & Software http://www.wescottdesign.com
Reply by ●October 11, 20122012-10-11
On 10/11/12 4:58 PM, Vladimir Vassilevsky wrote:> "Tim Wescott"<tim@seemywebsite.com> wrote: >> How commonly do you see PLL designs referred to as "type I", "type II", >> "type III", etc.? Do the terms make sense to you? > > IMO this terminology is used only in Gardner's book; there is no universal > meaning. > It is about P, PI, or PII control loop. Remnants of old times, when they > used to mix the details of implementation > with the type of the transfer function. > >> I'm writing a report; don't want to either baffle with bullshit nor leave >> out handy terms... > > Since nobody is going to read it anyway, why would that matter?ooooh! zinger! how do you know, Vlad? i am certainly interested in reading it. personally, Tim, if the difference in "type" is what is in the PID controller in the loop, i would just stick with "P", "I", and/or "D". like, for phase-linear FIR filters there are Type I, Type II, Type III, and Type IV. i know they have to do with all combinations of even-length vs. odd-length and even-symmetry vs. odd-symmetry. but i can't remember which Type goes with which combination, and i find the "Type" labeling useless because it is not descriptive. and i am not sure that all authors agree to the same convention, and that's when confusion really gets thick. -- r b-j rbj@audioimagination.com "Imagination is more important than knowledge."
Reply by ●October 11, 20122012-10-11
Tim Wescott wrote:> How commonly do you see PLL designs referred to as "type I", "type II", > "type III", etc.? Do the terms make sense to you? > > I'm writing a report; don't want to either baffle with bullshit nor leave > out handy terms... >Type I is the old vanilla version, type II with the charge pump and pulsing. Usually. But where have you read about a type III? Maybe this helps: http://www.sentex.ca/~mec1995/gadgets/pll/pll.html -- Regards, Joerg http://www.analogconsultants.com/
Reply by ●October 11, 20122012-10-11
On Thu, 11 Oct 2012 16:53:50 -0500, Tim Wescott <tim@seemywebsite.com> wrote:>On Thu, 11 Oct 2012 15:58:33 -0500, Vladimir Vassilevsky wrote: > >> "Tim Wescott" <tim@seemywebsite.com> wrote: >>> How commonly do you see PLL designs referred to as "type I", "type II", >>> "type III", etc.? Do the terms make sense to you? >> >> IMO this terminology is used only in Gardner's book; there is no >> universal meaning. >> It is about P, PI, or PII control loop. Remnants of old times, when they >> used to mix the details of implementation with the type of the transfer >> function. > >It certainly has universal meaning in control systems terms: it's the >number of integrating stages that are cascaded in the loop, either from >the compensator or the plant.I only encountered this recently when using a very old JPL paper that was pertinent to a problem we were dealing with. I had to look up the meaning, and they were using it like you do, to indicate the number of integrators in the loop. Most comm people that are familiar with PLLs would likely be more comfortable with describing a loop by its order, i.e., first order, second order, etc., which isn't exactly the same thing but seems to be the more widely understood terminology in my experience.> >I had to sweat through it in my undergraduate days, then help undergrads >sweat through it as a TA getting my Master's degree. > >>> I'm writing a report; don't want to either baffle with bullshit nor >>> leave out handy terms... >> >> Since nobody is going to read it anyway, why would that matter? > >Pbpbpbpbpbtht. It will become a cult classic among my customer's >customers, eagerly read and handed down from elder, competent and stately >engineers to youngsters who are wet behind the ears and trying to make >their systems match the performance of the existing ones in the field. > >-- >My liberal friends think I'm a conservative kook. >My conservative friends think I'm a liberal kook. >Why am I not happy that they have found common ground? > >Tim Wescott, Communications, Control, Circuits & Software >http://www.wescottdesign.comEric Jacobsen Anchor Hill Communications www.anchorhill.com
