What do you think?

Discussion in 'General Electronics Chat' started by R!f@@, Feb 20, 2011.

  1. R!f@@

    Thread Starter AAC Fanatic!

    Apr 2, 2009
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    I like members opinion on this.

    U have seen the components that are used in the motherboards, right?

    Do you think the SMD resistors and caps are of 1% tolerance types.

    Strict tolerance is essential for proper operation, am I right here?

    or they are just normal 5% types?
     
  2. Papabravo

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    Feb 24, 2006
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    On a motherboard I don't think the majority need to be 1% types since they are not used in analog circuits. Manufacturing techniques make it possible to achieve better and more consistent results. The conventional wisdom when when SMT components became prevalent in the mid 90s was that the cost of 1% components was the same as 5% components. From an inventory management perspective there was no reason not to use all 1% components.
     
  3. R!f@@

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    So U are saying they are usually 1% types.
     
  4. Papabravo

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    I think so the 1% types are the most prevalent in the marketplace. I think you have to try really hard to find 5% SMT resistors
     
  5. loosewire

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    Riaff,can't you the tolerants on the resistor,the color of the band
    tells you the tolerants.
     
  6. nerdegutta

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    Dec 15, 2009
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    I think he is asking for SMD components. I don't think there are color bands on SMD...:rolleyes:
     
  7. t06afre

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    It is hardly any markings at all. That is why a "tweezer" is a must then working with SMD components
    [​IMG]
     
  8. Markd77

    Senior Member

    Sep 7, 2009
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    Here's a big one Loosewire - the small ones are a quarter of this size. The number is the value - in this case 510K (51 x 10^4).

    I'm not sure what the tolerances on the caps are, I think 1% is unlikely, most smt caps are 10% or 20%.

    [​IMG]
     
  9. Papabravo

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    SMT(Surface Mount Technology) and SMD(Surface Mount Device) refer to the same kind of component.

    http://en.wikipedia.org/wiki/Surface-mount_technology

    Most resistors are 1%

    Caps traditionally came in Z5U, X7R, NPO/COG with increasingly tighter tolerance mostly as a function of temperature. I know there are other combinations of size an tolerance but I believe these are the most common for R's 'n C's
     
  10. R!f@@

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    Thanks guys...I have plenty of mobo's. I am salvaging the SMD's for my projects now.
     
  11. R!f@@

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    Hey....where can I get one of those..:D
     
  12. t06afre

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    The brand is "Smart Tweezers" Quite expensive but one of the best on the market https://smarttweezers.3dcartstores.com/Smart-Tweezers_c_1.html You will also find cheaper tweezers on the market. Some sell a tweezers that can be connected to a multimeter. The picture shows the device used in circuit. Personally I am always sceptic to measurements taken in circuit. As a thumb rule
     
  13. R!f@@

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    Woa!! that is way over my budget right now..
     
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