EIA Class 1 dielectric
From Wikipedia, the free encyclopedia
The EIA Class 1 dielectric materials are ceramic dielectric materials used in ceramic capacitors of small values (typ. <5 nF). The EIA Class 1 dielectrics in general are usually based on titanate formulas (usually titanium dioxide with calcium titanate) with low or zero content of barium titanate; due to its low content, their susceptibility to microphonics is low. (Cf. EIA Class 2 dielectric.) Their dependence on temperature is linear.
C0G (EIA) or NP0 (industry spec) is the material with the lowest capacitance/temperature dependence (Negative-Positive zero). C0G/NP0 dielectrics have the lowest losses, and are used in filters, as timing elements, and for balancing crystal oscillators. Ceramic capacitors tend to have low inductance because of their small size. NP0 refers to the shape of the capacitor's temperature coefficient graph (how much the capacitance changes with temperature). NP0 means that the graph is flat and the device is not affected by temperature changes. The C0G/NP0 material can be used up to gigahertz frequencies.
Common materials are C0G/NP0, P350, N1000/M3K.
The ceramic composition may involve one or more of dielectric electroceramics materials.
There are two naming conventions. The EIA version relies on letter-digit-letter code for the slope of the temperature-capacitance dependence. The industry version uses a N/P prefix (N for negative, P for positive) and the slope coefficient. See the comparison for some common materials:
| EIA | M7G | C0G | B2G | U1G | P2G | R2G | S2H | T2H | U2J | P3K | R3L |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Industry | P100 | NP0 | N030 | N075 | N150 | N220 | N330 | N470 | N750 | N1500 | N2200 |
The EIA three-character code for the material capacitance-temperature slope is derived from the low and high temperature limit, and the range of capacitance change.
| ppm/°C | Multiplier | Tolerance in ppm/°C (25-85 °C) |
|---|---|---|
| C: 0.0 | 0: -1 | G: ±30 |
| B: 0.3 | 1: -10 | H: ±60 |
| L: 0.8 | 2: -100 | J: ±120 |
| A: 0.9 | 3: -1000 | K: ±250 |
| M: 1.0 | 4: +1 | L: ±500 |
| P: 1.5 | 6: +10 | M: ±1000 |
| R: 2.2 | 7: +100 | N: ±2500 |
| S: 3.3 | 8: +1000 | |
| T: 4.7 | ||
| V: 5.6 | ||
| U: 7.5 |
