What is the difference between fixed and non-polarized capacitors? I’m slowly learning things and can’t find it, other than how it’s represented on a schematic.
Do you mean the difference between polarised and non-polarised capacitors?
Both are made in fixed capacitance values, but the former requires a DC voltage across it in order to maintain its polarisation.
You would normally find polarised capacitors in amplifier circuits where DC voltages are present, while non-polarised capacitors must be used in loudspeaker crossovers where no DC voltages are present.
Both are made in fixed capacitance values, but the former requires a DC voltage across it in order to maintain its polarisation.
You would normally find polarised capacitors in amplifier circuits where DC voltages are present, while non-polarised capacitors must be used in loudspeaker crossovers where no DC voltages are present.
Fixed is not a usual term for capacitors (since most are), though some are variable types, like in old radios.
Most electrolytic capacitors (and tantalum types) are polarized, which means the (+) terminal
can only have positive DC voltage on it relative to the negative terminal.
Some electrolytics are nonpolarized, because they contain two polarized capacitors connected
in series, but in opposite directions. Then the applied DC voltage polarity does not matter,
since one of the capacitors is always blocking the applied DC voltage. Sometimes the symbol
and package will have a (+) at both ends, or be marked NP for nonpolar, to emphasize that
either polarity of applied voltage is ok.
Most electrolytic capacitors (and tantalum types) are polarized, which means the (+) terminal
can only have positive DC voltage on it relative to the negative terminal.
Some electrolytics are nonpolarized, because they contain two polarized capacitors connected
in series, but in opposite directions. Then the applied DC voltage polarity does not matter,
since one of the capacitors is always blocking the applied DC voltage. Sometimes the symbol
and package will have a (+) at both ends, or be marked NP for nonpolar, to emphasize that
either polarity of applied voltage is ok.
Attachments
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Yes, film, nonpolar,or even bipolar can use a symbol like -ll-
Polar will usually be -l(- with a (+) on the left terminal.
Perhaps fixed in that book refers to a fixed polarity (not bipolar)
of electrolytic capacitor, but that is not a common usage.
Terminology and symbols in electronics can indeed vary somewhat
with the individual and country. Usually the BOM list for the circuit will clarify this.
https://www.nexpcb.com/blog/capacitor-symbols-explained
Polar will usually be -l(- with a (+) on the left terminal.
Perhaps fixed in that book refers to a fixed polarity (not bipolar)
of electrolytic capacitor, but that is not a common usage.
Terminology and symbols in electronics can indeed vary somewhat
with the individual and country. Usually the BOM list for the circuit will clarify this.
https://www.nexpcb.com/blog/capacitor-symbols-explained
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The | ( symbol is an alternative symbol for a capacitor. As Rayma says, the polarity would be indicated thus, +| (
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Note that the EU ('new') style and US ('old') style of capacitor symbols differ:
https://passive-components.eu/capac...cuit,th symbol for capacitor is used in japan.
https://passive-components.eu/capac...cuit,th symbol for capacitor is used in japan.
Electronic symbols have varied with time, country, and preferences of the individual.
Every schematic should have a BOM (bill of materials) which will clearly list
each part, description, mfr, value, mfr number, etc. Generally these are not listed on
the schematic, just the reference number like C3, R21, etc. This allows parts to be
revised without changing the schematic, and sometimes even the pcb.
Every schematic should have a BOM (bill of materials) which will clearly list
each part, description, mfr, value, mfr number, etc. Generally these are not listed on
the schematic, just the reference number like C3, R21, etc. This allows parts to be
revised without changing the schematic, and sometimes even the pcb.
In ordinary terms they are the same, however..
Electrolytic capacitors are constructed to take advantage of a layer of oxide between the plates which is inadvertently affected by the way you use them electrically.
I would love to see a picture of the full page talking "fixed" and "variable" and what is said about them.
The OP description is confused and confusing.
By definition, (or he wouldn´t be asking here), so instead of guessing what he "thinks" they say, I´d much prefer to read original writer´s words.
Don´t think it´s a copyright infringement posting just one page, and for didactic/educational purpose.
The OP description is confused and confusing.
By definition, (or he wouldn´t be asking here), so instead of guessing what he "thinks" they say, I´d much prefer to read original writer´s words.
Don´t think it´s a copyright infringement posting just one page, and for didactic/educational purpose.
Just got a book copy.
To say it lightly, that is a very poorly researched page.
Authors are not "electronics" guys but "Operations Manager - Cybernetics - Software Engineering" , authors on Arduino and Rabsperry programming and such.
I bet they wanted to fill up some pages and copypasted some stuff from OLD books, think 40´s or so (RDH4?), so they refer to componnts the old way and mention some which have not been used since the 30´s, when Radio was king and everyting else Eletronics just a side note.
some pearls:
* variable and split stator caps
* adjustable inductance transformer
* Adjustable coupling transformer (one coil slides inside the other ..... high Tech ... in 1924)
and so on 🙄
Meaning: do not lose sleep on the "Electronics" symbols and definitions used there.
To say it lightly, that is a very poorly researched page.
Authors are not "electronics" guys but "Operations Manager - Cybernetics - Software Engineering" , authors on Arduino and Rabsperry programming and such.
I bet they wanted to fill up some pages and copypasted some stuff from OLD books, think 40´s or so (RDH4?), so they refer to componnts the old way and mention some which have not been used since the 30´s, when Radio was king and everyting else Eletronics just a side note.
some pearls:
* variable and split stator caps
* adjustable inductance transformer
* Adjustable coupling transformer (one coil slides inside the other ..... high Tech ... in 1924)
and so on 🙄
Meaning: do not lose sleep on the "Electronics" symbols and definitions used there.
You can 'look inside' this modern and highly technical book on Amazon.
JMF has hit the nail on the head. 👍
The chart of electronic symbols does not match the style of the book, but appears to have been copied from a much older publication.
Perhaps this apparent sloppiness will be rectified in the 5th edition!
JMF has hit the nail on the head. 👍
The chart of electronic symbols does not match the style of the book, but appears to have been copied from a much older publication.
Perhaps this apparent sloppiness will be rectified in the 5th edition!
It has the TAB brand. In the 1970s TAB books were just awful, the lowest trash. A student brought me a question in one TAB book, and I was finding gross errors on 9 of 10 pages. I took the book away from him and gave him a better one (from another publishing brand).
People who didn't know better, school and town librarians, and booksellers, bought a lot of them. The TAB brand has been taken-over and used and abused while the general state of publishing declines. I bet part of TAB's "assets" is a portfolio(*) of artwork of stock drawings like those radio-symbols. OK, someone re-worked it to add digital ground, LED, tunnel diode. (Actually the Esaki is as old as TAB.)
(*)Possibly Encyclopedia of Electronics by Stan Gibilisco, which was named by the American Library Association in its list of "Best References of the 1980s"; note that librarians are not subject experts and don't know a cat's whisker from a PLL.
People who didn't know better, school and town librarians, and booksellers, bought a lot of them. The TAB brand has been taken-over and used and abused while the general state of publishing declines. I bet part of TAB's "assets" is a portfolio(*) of artwork of stock drawings like those radio-symbols. OK, someone re-worked it to add digital ground, LED, tunnel diode. (Actually the Esaki is as old as TAB.)
(*)Possibly Encyclopedia of Electronics by Stan Gibilisco, which was named by the American Library Association in its list of "Best References of the 1980s"; note that librarians are not subject experts and don't know a cat's whisker from a PLL.