Forums

Filter cap choice for ultra low ripple

Started by Cursitor Doom August 9, 2015
Gentlemen,

What is currently the best choice of filter capacitor for the PSU section 
of a high-end signal generator the output of which (obviously) really 
needs to be as ripple-free as humanly possible?
Just in *GENERAL* terms, please guys; don't want to get bogged down in 
specifics and calculations at this stage, please!

tia,
cd
On Sun, 9 Aug 2015 14:27:50 +0000 (UTC), Cursitor Doom
<curd@notformail.com> Gave us:

>Gentlemen, > >What is currently the best choice of filter capacitor for the PSU section >of a high-end signal generator the output of which (obviously) really >needs to be as ripple-free as humanly possible? >Just in *GENERAL* terms, please guys; don't want to get bogged down in >specifics and calculations at this stage, please! > >tia, >cd
In general terms.... You're an idiot on par with SkyTard Belching.
On Sun, 09 Aug 2015 11:09:01 -0400, DecadentLinuxUserNumeroUno wrote:

> On Sun, 9 Aug 2015 14:27:50 +0000 (UTC), Cursitor Doom > <curd@notformail.com> Gave us: > >>Gentlemen, >> >>What is currently the best choice of filter capacitor for the PSU >>section of a high-end signal generator the output of which (obviously) >>really needs to be as ripple-free as humanly possible? >>Just in *GENERAL* terms, please guys; don't want to get bogged down in >>specifics and calculations at this stage, please! >> >>tia, >>cd > > In general terms.... You're an idiot on par with SkyTard Belching.
Yeah, and you're a brainless troll with a long and very well-established track record.
On 8/9/2015 9:27 AM, Cursitor Doom wrote:
> Gentlemen, > > What is currently the best choice of filter capacitor for the PSU section > of a high-end signal generator the output of which (obviously) really > needs to be as ripple-free as humanly possible? > Just in *GENERAL* terms, please guys; don't want to get bogged down in > specifics and calculations at this stage, please! > > tia, > cd >
Capacitance as large as humanly possible.
On Sun, 9 Aug 2015 14:27:50 +0000 (UTC), the renowned Cursitor Doom
<curd@notformail.com> wrote:

>Gentlemen, > >What is currently the best choice of filter capacitor for the PSU section >of a high-end signal generator the output of which (obviously) really >needs to be as ripple-free as humanly possible? >Just in *GENERAL* terms, please guys; don't want to get bogged down in >specifics and calculations at this stage, please! > >tia, >cd
Roughly what frequency is the ripple at? Mains, 50kHz, 2MHz? Polymer electrolytics are pretty good, as are ceramic caps. More stages are better than fewer, and you can always use the cap multiplier gambit. Regulators with few-uV RMS noise are available. --sp -- Best regards, Spehro Pefhany Amazon link for AoE 3rd Edition: http://tinyurl.com/ntrpwu8 Microchip link for 2015 Masters in Phoenix: http://tinyurl.com/l7g2k48
On Sun, 9 Aug 2015 15:13:22 +0000 (UTC), Cursitor Doom
<curd@notformail.com> Gave us:

>On Sun, 09 Aug 2015 11:09:01 -0400, DecadentLinuxUserNumeroUno wrote: > >> On Sun, 9 Aug 2015 14:27:50 +0000 (UTC), Cursitor Doom >> <curd@notformail.com> Gave us: >> >>>Gentlemen, >>> >>>What is currently the best choice of filter capacitor for the PSU >>>section of a high-end signal generator the output of which (obviously) >>>really needs to be as ripple-free as humanly possible? >>>Just in *GENERAL* terms, please guys; don't want to get bogged down in >>>specifics and calculations at this stage, please! >>> >>>tia, >>>cd >> >> In general terms.... You're an idiot on par with SkyTard Belching. > >Yeah, and you're a brainless troll
I am not a troll, and I have orders of magnitude more electronic knowledge than you do.
> with a long and very well-established >track record.
What's the matter, dumbfuck? Does the truth hurt? Filtering ripple takes more than a simple "filter cap" or "filter cap choice", you retarded putz. You sport about the same 'intelligence' about electronics as Donald Trump does on US history, or foreign policy or political posture. He is an absolute idiot, and you are right there in the same class. You and "a high end signal generator" are two things that are mutually exclusive. So your grasp of what internals are needed in one are pretty far apart as well. Particularly if you are so dumb (in electronics)that you need to come in here and ask such a question, which reveals just how ill equipped you are for completing any such design task. And as far as my "track record" goes, it only puts the pinch on abject idiots such as yourself. Go somewhere else and spread your stench. In here you are transparent, and you asking such a low end, poorly worded revealing question makes you quite transparent, and obviously not equipped to tackle such a complex design as a "high end signal generator". So yeah, punk... you are on par with the SkyTard, who has been invading several newsgroups with his utter stupidity. And that is despite the fact that your question is on topic here. It simply exposes such how simple your skill level is. Quit while you are ahead., or your 'ultra low' profile of stupidity will get raised. ooops... too late.
On 8/9/2015 10:27 AM, Cursitor Doom wrote:
> Gentlemen, > > What is currently the best choice of filter capacitor for the PSU section > of a high-end signal generator the output of which (obviously) really > needs to be as ripple-free as humanly possible? > Just in *GENERAL* terms, please guys; don't want to get bogged down in > specifics and calculations at this stage, please!
Ripple is determined by two factors. One is the capacitance relative to the amount of ripple current flowing and the frequency. The other is the ESR of the cap relative to the peak current. Ceramic caps have the lowest ESR of caps commonly used for PSU outputs. Electrolytic caps provide more capacitance at a lower price. Sometimes the best tradeoff is a combination, other times ceramic caps alone will do the job well enough. The only ways to know are to do the calculations or to build it both ways and measure the ripple. :) -- Rick
On Sun, 9 Aug 2015 15:13:22 +0000 (UTC), Cursitor Doom
<curd@notformail.com> wrote:

>On Sun, 09 Aug 2015 11:09:01 -0400, DecadentLinuxUserNumeroUno wrote: > >> On Sun, 9 Aug 2015 14:27:50 +0000 (UTC), Cursitor Doom >> <curd@notformail.com> Gave us: >> >>>Gentlemen, >>> >>>What is currently the best choice of filter capacitor for the PSU >>>section of a high-end signal generator the output of which (obviously) >>>really needs to be as ripple-free as humanly possible? >>>Just in *GENERAL* terms, please guys; don't want to get bogged down in >>>specifics and calculations at this stage, please! >>> >>>tia, >>>cd >> >> In general terms.... You're an idiot on par with SkyTard Belching. > >Yeah, and you're a brainless troll with a long and very well-established >track record.
Doesn't Pan offer filtering? In Agent I just killfile DecadentLoser so that I'm not exposed to his (or other loser's :-) rants.... keeps me calm and my blood pressure low >:-} The only time I see his rants is when you feed the troll :-( ...Jim Thompson -- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | San Tan Valley, AZ 85142 Skype: skypeanalog | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | I love to cook with wine. Sometimes I even put it in the food.
If you can afford a volt or so of loss, a 2-stage cap multiplier is the ticket. You can get way over 120 dB rejection of SMPS frequencies. 

Cheers

Phil Hobbs
On Sun, 09 Aug 2015 11:31:04 -0400, DecadentLinuxUserNumeroUno
<DLU1@DecadentLinuxUser.org> wrote:

>On Sun, 9 Aug 2015 15:13:22 +0000 (UTC), Cursitor Doom ><curd@notformail.com> Gave us: > >>On Sun, 09 Aug 2015 11:09:01 -0400, DecadentLinuxUserNumeroUno wrote: >> >>> On Sun, 9 Aug 2015 14:27:50 +0000 (UTC), Cursitor Doom >>> <curd@notformail.com> Gave us: >>> >>>>Gentlemen, >>>> >>>>What is currently the best choice of filter capacitor for the PSU >>>>section of a high-end signal generator the output of which (obviously) >>>>really needs to be as ripple-free as humanly possible? >>>>Just in *GENERAL* terms, please guys; don't want to get bogged down in >>>>specifics and calculations at this stage, please! >>>> >>>>tia, >>>>cd >>> >>> In general terms.... You're an idiot on par with SkyTard Belching. >> >>Yeah, and you're a brainless troll > > I am not a troll, and I have orders of magnitude more electronic >knowledge than you do.
You are an imbecile.
> >> with a long and very well-established >>track record. > > What's the matter, dumbfuck? Does the truth hurt? > > Filtering ripple takes more than a simple "filter cap" or "filter cap >choice", you retarded putz. > > You sport about the same 'intelligence' about electronics as Donald >Trump does on US history, or foreign policy or political posture. He is >an absolute idiot, and you are right there in the same class. > > You and "a high end signal generator" are two things that are mutually >exclusive. So your grasp of what internals are needed in one are pretty >far apart as well. > > Particularly if you are so dumb (in electronics)that you need to come >in here and ask such a question, which reveals just how ill equipped you >are for completing any such design task. > > And as far as my "track record" goes, it only puts the pinch on abject >idiots such as yourself. > > Go somewhere else and spread your stench. > > In here you are transparent, and you asking such a low end, poorly >worded revealing question makes you quite transparent, and obviously not >equipped to tackle such a complex design as a "high end signal >generator". > > So yeah, punk... you are on par with the SkyTard, who has been >invading several newsgroups with his utter stupidity. > > And that is despite the fact that your question is on topic here. It >simply exposes such how simple your skill level is. Quit while you are >ahead., or your 'ultra low' profile of stupidity will get raised. >ooops... too late.