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Is an AD converter a type of encoder/decoder?

  1. Apr 11, 2012 #1

    Femme_physics

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    According to wiki:

    So can we call an AD converter an encoder?
     
  2. jcsd
  3. Apr 11, 2012 #2
    Not very common, but you can categorize as encoder.....From analog to digital encoder.
     
  4. Apr 11, 2012 #3

    Bobbywhy

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    I agree, an A/D converter is exactly an encoder. So is a D/A converter. Both fit the definition you posted.
     
  5. Apr 11, 2012 #4
    Hmm. After all A/D converter gives you a code. So its an encoder. But I think the D/A converter will be decoder.
     
  6. Apr 11, 2012 #5

    Bobbywhy

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    the wiki definition posted in the OP is quite general:

    "An encoder is a device, circuit, transducer, software program, algorithm or person that converts information from one format or code to another, for the purposes of standardization, speed, secrecy, security, or saving space by shrinking size."

    IMO, it includes The D/A converter as well.
     
    Last edited: Apr 11, 2012
  7. Apr 11, 2012 #6
    Well, I did not fully read the portion about "one format or code". In that case, both A/D and D/A converter will be encoder as well as decoder.
     
  8. Apr 11, 2012 #7

    Bobbywhy

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    Koldshare: No Problemo. I often don't see obvious stuff the older I get...some call it "a senior moment". Ha Ha.

    Bobbywhy
     
  9. Apr 11, 2012 #8

    Femme_physics

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    I'm glad there is an agreement on this :) I wish wiki defined an A/D converter as such.
     
  10. Apr 11, 2012 #9

    sophiecentaur

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    I don't think it really matters as the term is not strictly defined and mainly a matter of fashion.
    No, if you want me to get picky about the terms that people use for really important issues . . . . . .:smile:
     
  11. Apr 11, 2012 #10

    Femme_physics

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    Fair enough, I'm just trying to put things in categories... you know, maintaining some order in my notes :) Thanks for the replies!
     
  12. Apr 11, 2012 #11

    sophiecentaur

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    Just remember, Physics is not botany. It's relationships not classification that drive Physics.

    Apologies to any eminent passing botanists but I remember reading that Niuclear Physics (this was in the Early 20the Century) was getting to be a bit like Botany as they were just finding more and more species of Nuclear Stuff and had nowhere to put them. At least they're beginning to pull it all together these days.
     
  13. Apr 11, 2012 #12

    phinds

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    Personally, I think that calling an A/D converter an "encoder" is being pretty liberal with the term. I always think of an encoder as a device that takes some form of information (an output of a transducer, say) and encodes it in some form of electrical code (such as PCM). That MAY be an overly strict interpretation, but I think it avoids confusion.
     
  14. Apr 11, 2012 #13

    sophiecentaur

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    So where would a 'position encoder' fit? You can buy them.

    Classification is supposed to be our servant and not our master.
     
  15. Apr 11, 2012 #14
    I think the definition you're using could be applied to an A/D, but no one ever calls an A/D by itself an encoder and it will just confuse people. Also, I think an A/D has a very specific purpose and definition, and it should not be lumped in with other components called encoders. Likewise, encoders have very specific purposes in electronics, and rarely would the word encoder pop into someone's head when they are thinking of converting an analog voltage to a digital value, at least in that immediate step.

    "for the purposes of standardization, speed, secrecy, security, or saving space by shrinking size". I think in this last part, you could cross out speed, secrecy, security, and saving space (unless you consider a complete analog design as taking more space than digital). The only purpose that might fit an ADC is standardization since the rest of a system could use digital values as a standard.

    For example, is a television an encoder by that definition? It converts complicated analog electrical signals to audio and light signals which are the standard format humans use to view that information. I can't wait to get home and watch the simpsons on my voltage to photon encoder tonight.
     
    Last edited: Apr 11, 2012
  16. Apr 11, 2012 #15

    sophiecentaur

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    If a TV system were used for OCR, reading handwritten symbols and converting them to ASCII then it would, undoubtedly be an ENCODER. It is were used to watch a football match then, perhaps not. If it were used to keep a door open then it could be called a DOOR STOP. Why does this matter so much?
    We're talking Editorial Style here, not Physics or Engineering.
     
  17. Apr 11, 2012 #16

    Femme_physics

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    QUOTE OF THE YEAR!!!

    :approve:
     
  18. Apr 11, 2012 #17
    Well, that's sort of the point, calling an ADC an encoder doesn't mean much. It may be beneficial to think of an ADC as an encoder for conceptual or learning reasons, and it may give rise to new ideas on how to use an ADC. But, I think it is being conservative to reject calling an ADC an encoder when an ADC has a very specific function and purpose.
     
  19. Apr 11, 2012 #18

    sophiecentaur

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    Mwah!!!
    I love you all.
    :blushing:
     
  20. Apr 11, 2012 #19

    sophiecentaur

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    You are just too late to start getting this straightened out, I'm afraid. If you can buy something on EBAY called an optical encoder (which is an ADC by any standard) then Encoder is a word that has an established (although, possibly offensive) use when applied to some forms of ADC.

    A the kids say: "Get over it"
     
  21. Apr 11, 2012 #20

    jim hardy

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    Some folks call this a handle
    some call it a torque amplifier

    http://cdn4.stanleysupplyservices.com/images/p/127-920.01_s310_p1._Vdfedaa6d_.jpg [Broken]

    when in Rome...
     
    Last edited by a moderator: May 5, 2017
  22. Apr 11, 2012 #21
    IMO, by itself no, due to the 'purposes' spec. A DAC or ADC doesn't serve to standardize, speed up, make secret, secure, or shrink anything. It merely converts one signal type to another. I also wouldn't call a rectifier an encoder nor an inverter a decoder.

    sophiecentaur, your example of an optical encoder, IMO, is different. The optical encoder has the specific purpose of translating signal pulses into a position.
     
  23. Apr 11, 2012 #22

    sophiecentaur

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    Other way round?
    The position of the shaft isn't a secret. haha
     
  24. Apr 11, 2012 #23

    NascentOxygen

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    IMO, the ADC would be a digital encoder; and the DAC would be an analog decoder. :smile:
     
  25. Apr 11, 2012 #24

    OldEngr63

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    Well, just to be disagreeable, I will suggest that it does not meet the definition of the encoder as given. The last part of the definition had the words, ".... by shrinking size." What is the size of the analog signal? Until we can clearly define the size of the analog signal, I see no way to verify that the size is reduced.

    Not that I can see that any of this is too important.
     
  26. Apr 11, 2012 #25

    sophiecentaur

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    You always reduce the amount of information in an analogue signal when you digitally 'encode' it, however high the sample rate or the number of levels used.
     
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