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I'm trying to understand this schematics section related with a micro-usb connection:

enter image description here

I have three questions:

  1. Why are the resistors with 0R? Is this a convention for a particular value?
  2. Which electronic component is F1?
  3. The same as 2 but for FB1.
Miguel
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  • zero ohms resistors are jumpers or functional placeholders in case a resistor ends up being needed somewhere – DKNguyen Jun 14 '20 at 18:29

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Why are the resistors with 0R?

That's a very common notation: R is for "resistor", and is placed where the decimal point in the component value in ohm would be (because Ω was hard to produce back in the day). This is a 0 Ω resistor – in case you analyze your device and figure out later that a USB-compliant termination resistor is actually necessary.

Which electronic component is F1?

What is the schematic symbol for resettable fuses?

Which electronic component is FB1?

https://electronics.stackexchange.com/search?q=schematic+symbol+FB

Marcus Müller
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  • Ok, thanks. But in that case why put a 0 resistor? Isn't 0 ohm resistor the same as not having a resistor at all? – Miguel Jun 14 '20 at 18:32
  • I've answered exactly that. Please read the full paragraph. – Marcus Müller Jun 14 '20 at 18:36
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    @Miguel For insurance. Jumpers are like guns when boarding derelict alien spaceships. Sometimes you would rather have it and not need it than need it and not have it. – DKNguyen Jun 14 '20 at 18:37
  • @MarcusMüller I think that the paragraph you wrote should be very clear for someone who is not a newbie in electronics, which is not my case. It was the case I think I wouldn't write the initial question... – Miguel Jun 14 '20 at 18:42
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    @Miguel I kind of agree...you probably doesn't know what a termination is. – DKNguyen Jun 14 '20 at 18:46
  • @MarcusMüller I'm not sure "R" is for resistor. It's also used for inductors (eg. 2R2 for 2.2uH). Without googling it, I'd guess it might stand for "Radix" (as in radix point), but that's a guess. Eaton says R = decimal point. Or maybe it's just some ad hoc thing that they started to do with inductors (perhaps more likely). – Spehro Pefhany Jun 14 '20 at 20:20
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    @SpehroPefhany ah, true, interesting. Never thought of that. But, also, never saw a 10µF capacitor labeled with 10R0 or something similar – Marcus Müller Jun 15 '20 at 08:26