Difference between X7R, X5R, X8R, Z5U,Y5V, X7S, C0G Capacitor dielectrics
Ceramic capacitors are broadly categorized into 4 classes based on the dielectrics used in them,
- Class 1
- Class 2
- Class 3
- Class 4
Class 3 and Class 4 capacitors are not widely used and hence have not been standardized.
Class 1 Capacitors :
Class 1 capacitors have following characteristics,
- Linear temperature coefficient : Their capacitance varies linearly with temperature
- No Voltage dependency : Their capacitance does not depend on the applied voltage
- No Aging : They do not suffer significant aging process due to para electric materials used in manufacturing
- No electrical losses : Have significantly low electrical losses compared to Class 2 capacitors
- Used in High Q filters : Due to the above properties they are used in applications like resonant circuits, PLL and Oscillators.
- Have high stability and accuracy
They use a 3 digit notation to indicate the dielectric used in them according to EIA RS-198 standard
C0G
| | |
| | |– Tolerance
| |—- Multiplier
|—— Coeffcient
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.
Similarly, When manufacturer says that this is a Y5V capacitor, it means that the capacitor can operate from -30 degrees centigrade to +85 degrees centigrade temperature and the capacitance of the capacitor will not increase more than 22% and not decrease below 82% from its nominal value.
Most commonly used capacitor dielectrics are X7R,X8R,X5R,Y5V,Z5U,X7S.
Although Class 1 capacitors have more advantages than Class 2 capacitors, I encounter more X7R and X5R capacitors on day to day basis than C0G capacitors.