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Use resistor instead of regulator?

Started by John Doe January 30, 2021
I can put a resistor after a voltage that's too high for the circuit?

Of course the resistor must handle the current.

A decoupling capacitor after the resistor.

Any problems with that?

Thanks.
On 2021-01-30, John Doe <always.look@message.header> wrote:
> I can put a resistor after a voltage that's too high for the circuit? > > Of course the resistor must handle the current. > > A decoupling capacitor after the resistor. > > Any problems with that?
If the capacitor is needed there probably are problems. In the spirit of your question that is all I will say. -- Jasen.
John Doe <always.look@message.header> wrote:
> I can put a resistor after a voltage that's too high for the circuit? > > Of course the resistor must handle the current. > > A decoupling capacitor after the resistor. > > Any problems with that?
If your load has a variable current draw, then you will also have a variable voltage on the load side of the resistor.
Rich wrote:

> John Doe wrote:
>> I can put a resistor after a voltage that's too high for the circuit? >> >> Of course the resistor must handle the current. >> >> A decoupling capacitor after the resistor. >> >> Any problems with that? > > If your load has a variable current draw, then you will also have a > variable voltage on the load side of the resistor.
If it's a big capacitor, the voltage variation is minimal?
John Doe <always.look@message.header> wrote:
> Rich wrote: > >> John Doe wrote: > >>> I can put a resistor after a voltage that's too high for the circuit? >>> >>> Of course the resistor must handle the current. >>> >>> A decoupling capacitor after the resistor. >>> >>> Any problems with that? >> >> If your load has a variable current draw, then you will also have a >> variable voltage on the load side of the resistor. > > If it's a big capacitor, the voltage variation is minimal?
No, the size of the capacitor simply determines the rate at which the voltage changes. Given a current draw change of sufficient length in time (length determined by capicator size), the voltage across the capacitor will settle to that which remains after the new drop across the resistor. Wire up a test circuit on a breadboard and measure the changes yourself.
Rich <rich@example.invalid> wrote:

> John Doe wrote: >> Rich wrote: >>> John Doe wrote: >> >>>> I can put a resistor after a voltage that's too high for the circuit? >>>> >>>> Of course the resistor must handle the current. >>>> >>>> A decoupling capacitor after the resistor. >>>> >>>> Any problems with that? >>> >>> If your load has a variable current draw, then you will also have a >>> variable voltage on the load side of the resistor. >> >> If it's a big capacitor, the voltage variation is minimal? > > No, the size of the capacitor simply determines the rate at which the > voltage changes.
Then your answer should be "Yes", given the same amount of time. Why are you fighting this? Do you think it makes you look smart?
John Doe <always.look@message.header> wrote:
> Rich <rich@example.invalid> wrote: > >> John Doe wrote: >>> Rich wrote: >>>> John Doe wrote: >>> >>>>> I can put a resistor after a voltage that's too high for the >>>>> circuit? >>>>> >>>>> Of course the resistor must handle the current. >>>>> >>>>> A decoupling capacitor after the resistor. >>>>> >>>>> Any problems with that? >>>> >>>> If your load has a variable current draw, then you will also have >>>> a variable voltage on the load side of the resistor. >>> >>> If it's a big capacitor, the voltage variation is minimal? >> >> No, the size of the capacitor simply determines the rate at which >> the voltage changes. > > Then your answer should be "Yes", given the same amount of time.
No, the correct answer is "no". The voltage variation can be substantial. Rate of change is a different measure than voltage magnitude.
> Why are you fighting this?
Note that I could ask you the same question. My answer is correct, yours is incorrect.
No, thanks anyway...

-- 
Rich <rich@example.invalid> wrote:

> Path: eternal-september.org!reader02.eternal-september.org!.POSTED!not-for-mail > From: Rich <rich@example.invalid> > Newsgroups: sci.electronics.basics > Subject: Re: Use resistor instead of regulator? > Date: Mon, 1 Feb 2021 14:59:53 -0000 (UTC) > Organization: A noiseless patient Spider > Lines: 35 > Message-ID: <rv9519$1l9$1@dont-email.me> > References: <rv455v$6ho$1@dont-email.me> <rv4oh1$cfb$1@dont-email.me> <rv6617$2rs$9@dont-email.me> <rv6ijs$qed$1@dont-email.me> <rv8ogi$sku$8@dont-email.me> > Injection-Date: Mon, 1 Feb 2021 14:59:53 -0000 (UTC) > Injection-Info: reader02.eternal-september.org; posting-host="d71d69244b44f2167a5474a852a92cea"; logging-data="1705"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18WDlUwqnHhTSdJSoCqQnVy" > User-Agent: tin/2.0.1-20111224 ("Achenvoir") (UNIX) (Linux/3.10.17 (x86_64)) > Cancel-Lock: sha1:LBNwrlosj8h+C/mmb8/JDn9V+kU= > Xref: reader02.eternal-september.org sci.electronics.basics:55501 > > John Doe <always.look@message.header> wrote: >> Rich <rich@example.invalid> wrote: >> >>> John Doe wrote: >>>> Rich wrote: >>>>> John Doe wrote: >>>> >>>>>> I can put a resistor after a voltage that's too high for the >>>>>> circuit? >>>>>> >>>>>> Of course the resistor must handle the current. >>>>>> >>>>>> A decoupling capacitor after the resistor. >>>>>> >>>>>> Any problems with that? >>>>> >>>>> If your load has a variable current draw, then you will also have >>>>> a variable voltage on the load side of the resistor. >>>> >>>> If it's a big capacitor, the voltage variation is minimal? >>> >>> No, the size of the capacitor simply determines the rate at which >>> the voltage changes. >> >> Then your answer should be "Yes", given the same amount of time. > > No, the correct answer is "no". The voltage variation can be > substantial. Rate of change is a different measure than voltage > magnitude. > >> Why are you fighting this? > > Note that I could ask you the same question. My answer is correct, > yours is incorrect. > > >
On 2/02/2021 4:11 am, John Doe wrote:
> No, thanks anyway... >
So bugger off and do it know it all.You don't need advice from us humble mortals !!
Lots of reasons for non-answers, crappy answers, and venting. When a group 
is dying, for example. Non-answers are entirely understandable and no 
problem with me. Normally, people answer questions because they like the 
question, and because they want to see their writing on USENET. Then there 
are not-quite-grown-ups who love playing with an imaginary kill file 
friend (they are not skilled enough to control). 

This netcop wannabe troll can go fuck itself... 

-- 
RheillyPhoull <Rheilly@bigslong.com> wrote:

> Path: eternal-september.org!reader02.eternal-september.org!xmission!news.snarked.org!border2.nntp.dca1.giganews.com!nntp.giganews.com!buffer2.nntp.dca1.giganews.com!nntp.westnet.com.au!news.westnet.com.au.POSTED!not-for-mail > NNTP-Posting-Date: Mon, 01 Feb 2021 19:55:35 -0600 > Subject: Re: Use resistor instead of regulator? > Newsgroups: sci.electronics.basics,free.spam > References: <rv455v$6ho$1@dont-email.me> <rv4oh1$cfb$1@dont-email.me> <rv6617$2rs$9@dont-email.me> <rv6ijs$qed$1@dont-email.me> <rv8ogi$sku$8@dont-email.me> <rv9519$1l9$1@dont-email.me> <rv9na2$thk$2@dont-email.me> > From: RheillyPhoull <Rheilly@bigslong.com> > Date: Tue, 2 Feb 2021 09:55:34 +0800 > User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.7.0 > MIME-Version: 1.0 > In-Reply-To: <rv9na2$thk$2@dont-email.me> > Content-Type: text/plain; charset=utf-8; format=flowed > Content-Language: en-US > Content-Transfer-Encoding: 7bit > Message-ID: <mOqdnViuHfaKLIX9nZ2dnUU7-dudnZ2d@westnet.com.au> > Lines: 5 > X-Usenet-Provider: http://www.giganews.com > NNTP-Posting-Host: 106.69.177.15 > X-Trace: sv3-FcLxUF6QNWGWX0JZWCAqzZeFnCSRzIQzxdQPKKU/ouvaIlWI81kWv1URdSDv8QPTWUxiVuwood7EFam!ntsViOraSWMiGNeU3PvZ3jmOjBPT5/oLAtbfIqEIZzAjdGLnmekbgEeq7GqPIUaiW+h0rJwIdL2y!gpMhtQDdJlzT+lDzBVi9 > X-Complaints-To: abuse@westnet.com.au > X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers > X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly > X-Postfilter: 1.3.40 > X-Original-Bytes: 1542 > Xref: reader02.eternal-september.org sci.electronics.basics:55503 free.spam:14046 > > On 2/02/2021 4:11 am, John Doe wrote: >> No, thanks anyway... >> > So bugger off and do it know it all.You don't need advice from us humble > mortals !! > >