Avx surface mount mlccs are available in both class 1 and class 2 formulations.
Ceramic capacitor temperature coefficient x7r.
Its temperature variation of capacitance is within 15 from 55 c to 125 c.
Figure 5 illustrates the typical capacitance response over temperature for tantalum capacitors class 2 ceramic x7r capacitors and class 1 ceramic np0 or c0g capacitors.
The first character indicates the lowest temperature that the capacitor can handle.
The tantalum capacitor exhibits linear capacitance change with respect to temperature.
X7r formulations are called temperature stable ceramics and fall into eia class ii materials.
The typical aging of x7r ceramic capacitors is about 2 5 per decade the aging rate of z5u ceramic capacitors is significantly higher and can be up to 7 per decade.
Details about the layers used in a ceramic capacitor s construction can be found in the series datasheet.
X7r is the most popular of these intermediate dielectric constant materials.
Similarly when manufacturer says that this is a y5v capacitor it means that the capacitor.
The letter x as in x7r x5r corresponds to 55 c.
5 as in x5r corresponds to 85 c and 7 as in x7r corresponds to 125 c.
5 capacitance change at 55 c to 8 at 125 c.
X7r x7s ceramic capacitors.
This capacitance change is non linear.
Avx offers a wide range of surface mount mlccs for commercial applications to mission critical.
A rule of thumb is the higher the temperature dependence of the ceramic the higher the aging percentage.
The second character indicates the maximum temperature.
For example an image like this is found in the commercial x7r surface mount ceramic capacitor datasheet.
Within the ceramic capacitor family there are many forms of ceramic dielectric that are used.
The theoretical range is from 45 c to 200 c.
Temperature compensating formulation are class 1 and temperature stable and general application formulations are classified as class 2.
So according to the above table when manufacturer says that this is a x7r capacitor it means that the capacitor can operate from 55 degrees centigrade to 125 degrees centigrade temperature and the capacitance of the capacitor will not vary more or less than 15 from its nominal value specified.
Diagram showing construction with standard termination.