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This question is in the context of a production environment where part numbers and change notices are strictly controlled, and any alternate manufacturer parts under an internal part number must be equivalent components.

For Class 2 Dielectrics, the rating codes are well defined. When requesting a new part number X5R and X7R are not equivalent are are given different internal part numbers (even if they are valid substitutes in a given design).

For Class 1 Dielectrics the picture to me is a little fuzzy. I recognize that there are a few different dielectric codes associated with Class 1 parts.However, C0G and NP0 specifically are used by some manufacturers interchangeably. Also, some distributor search engines (e.g. Digikey) will give option as NP0/C0G when filtering capacitors.

As an example there are two equivalent parts from TDK, an 0603 1000pF Capacitor. One is sold under NP0 designation the other under C0G, their spec sheets are identical...

C1608NP01H102J080AA

C1608C0G1H102J080AA

My question is, when applying the most stringent view of production Change Control and Controlled Part Numbers, Could NP0 and C0G be considered equivalent or synonymous?

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  • \$\begingroup\$ I don't know how responsive TDK is to questions, but given they're apparently publishing two different datasheets, you might be able to reach out to a sales engineer or equivalent and see what they say. \$\endgroup\$
    – mbrig
    Feb 2, 2019 at 10:36

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Yes they are equivalent.

C0G is the material class that gives an NP0 (NP-zero ) tempco. But it is slang (NP-oh) where the 0 looks like O.

Beware that it is often spelt both ways with oh or zero, but it is intended to be a zero in both cases.

They also have P100 for +100 ppm/‘C and N100, N200 etc for -PPM over a greater range since ceramics tend to be offset this way. The ceramic composition is varied for analog applications requiring this .

C0G: Normally used for low C values. It has a low dielectric constant, but highest level of stability vs T and Vdc
X7R: Used for high C values with much higher dielectric constant than COG, but a lower stability.
Z5U: Used for even higher C values but has a lower stability than either COG or X7R, thus lower costs

The other tempco ratings that are below NP0 have different alpha-numeric codes. eg. P2H R2H S2H etc

see Murata specs

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  • \$\begingroup\$ I know NP0 is always a zero, but is it COG (with the letter) or C0G (with the number)? \$\endgroup\$
    – Hearth
    Feb 2, 2019 at 14:31
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    \$\begingroup\$ It is both with zeroes, like Canadian postal codes, there are other codes in Murata’s link for different tempco that indicates the chemistry thermal properties besides 0 which each have a 50ppm tolerance. It’s just faster to read as “oh” \$\endgroup\$ Feb 2, 2019 at 16:35
  • \$\begingroup\$ Also notice only the “Code” font shows the zero best. \$\endgroup\$ Feb 2, 2019 at 17:27

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