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Capacitor marking with line underneath; these aren't tantalum (I don't think anyway), so I'm not sure which units the capacitance is written in.

Capacitor marking with line underneath

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    \$\begingroup\$ How come you only considered options pF and µF? What about nF (which lies inbetween magnitude wise)? \$\endgroup\$
    – MEMark
    Commented Jul 1, 2023 at 7:31
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    \$\begingroup\$ @MEMark From what I've heard, the capacitance of a capacitor is often described in terms of pF or µF, but rarely in terms of nF. \$\endgroup\$ Commented Jul 2, 2023 at 4:20

3 Answers 3

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That is a ceramic disc capacitor, 47 pF.

Here's a datasheet for a typical capacitor of this type: enter image description here
https://www.vishay.com/docs/28515/sseries.pdf


A good clue: The two capacitors, crystal, and resistor appear to be an oscillator circuit, perhaps for the IC next to them; in this use the capacitors are almost always a few 10s of pF.

This circuit is from ST's excellent oscillator design guide for these AN 2867 enter image description here

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    \$\begingroup\$ Thanks to everyone who commented! Yes, good eye. It's in a Pierce Oscillator, and the IC is a hex inverter. The hand-drawn circuit sketch I received mislabelled it as microF, and I am very pleased that this might be what could fix my issue! \$\endgroup\$ Commented Jun 30, 2023 at 12:36
  • \$\begingroup\$ To check, will having a much larger sets of capacitors connected to this circuit, potentially cause damage to the components? \$\endgroup\$ Commented Jun 30, 2023 at 12:39
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    \$\begingroup\$ Generally it's good to keep question separate: can I suggest you post a new question with a diagram of what you're asking? \$\endgroup\$
    – jonathanjo
    Commented Jun 30, 2023 at 12:41
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    \$\begingroup\$ @ShashvatVerma Larger capacitance values should not damage anything, however the circuit will likely not oscillate. Check electrical description of Pierce oscillator. The capacitors & crystal form a tank circuit that needs a certain balance of values. \$\endgroup\$
    – pwrgreg007
    Commented Jul 2, 2023 at 16:59
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Encoding for Ceramic Capacitors

Ceramic capacitors encoding consists 1-3 digits.

If the capacitor code consist only 1 or 2 digits, it is simply their capacitance value in PicoFarads (pF). For example if a ceramic capacitor has a code ‘5’ and other has ‘47’, their respective capacitance values are 5 pF and 47 pF.

Source: https://circuitdigest.com/calculators/capacitor-value-code-calculator

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That is a ceramic disc capacitor, normally you would have three figures on it, and the value is in pF; 470 means 47 x 10^0 = 47 pF, 102 = 10 x 10^2 = 100 pF and so on.

I suppose in this case they just omitted the 0 for some reason.

Rest assured it is not a 47 µF capacitor

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