Square resistors on circuit boards?

Discussion in 'General Electronics Chat' started by seanspotatobusiness, Sep 13, 2017.

  1. seanspotatobusiness

    Thread Starter Member

    Sep 17, 2016
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    Why do some circuit boards have square resistors?

    [​IMG]
     
  2. WBahn

    Moderator

    Mar 31, 2012
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    Because whoever designed the circuit and/or the board chose to use them....?
     
  3. crutschow

    Expert

    Mar 14, 2008
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    Those look like they have low resistance values (2.2Ω and 0.82Ω) and it may be easier to make them in a small square package since they would have a short resistance element.
     
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  4. panic mode

    Senior Member

    Oct 10, 2011
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    they run out of donut, sphere and pyramid shaped resistors?
     
    Robin Mitchell likes this.
  5. JUNELER

    Member

    Jul 13, 2015
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    Hi,
    Resistance value is more important .shapes dont mind it.As long manufactures designed the accuracy is next valued.
     
  6. WBahn

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    Yes and no. For many circuits, parasitics are very important and thus not only can how the component is manufactured be extremely important, but also how the component is laid out on the board both relative to the board and its traces and relative to the other components.
     
  7. kubeek

    AAC Fanatic!

    Sep 20, 2005
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    I think those are actually inductors.
     
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  8. WBahn

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    The form factor might suggest it, but do they mark inductors with an 'R' for the decimal point?

    And what would the values be? 2.2 H??? I suppose a convention might be that it has in implied scaling prefix, like many picofarad capacitors do.

    I haven't run into too many components marked with this convention (and no inductors, that I recall) but on schematics I've usually seen R used as the radix for resistors, F for capacitors, and H for inductors.

    But certainly a noteworthy observation.
     
  9. kubeek

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    WBahn likes this.
  10. crutschow

    Expert

    Mar 14, 2008
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    Very odd that they use R as a decimal point for an inductor.
    Seems like it was done by some manufacturer who doesn't understand marking convention.
     
  11. WBahn

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    Possibly. But if so, it would only serve to further emphasize the oft repeated admonitions about assuming that component markings follow some rigid convention.
     
  12. bertus

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  13. WBahn

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    The first time I came across the R notation, I thought it means "radix", but I was told it meant "resistor" and they pointed out some F and H (on schematics). I've even seen schematics that use Ω on resistors (you'd be insane to use O for ohms). Now I'm wondering if perhaps I wasn't that far off in thinking of the R as the radix when no scaling prefix is appropriate.
     
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