Ceramic Capacitor Dielectric Characteristics – NPO, X7R, Z5U and Y5U

Overview

Ceramic capacitors are categorized by dielectric material, which directly determines capacitance stability versus temperature, applied voltage, and operating frequency.
Common dielectric classifications include NPO, X7R, Z5U, and Y5U.
Understanding these material characteristics is essential for proper component selection.

Capacitance Change vs Temperature

Dielectric type defines how capacitance varies with ambient temperature:

• NPO – Highly stable dielectric with minimal capacitance change over temperature.
• X7R – Moderate stability, suitable for general-purpose applications requiring balanced performance.
• Z5U – Higher capacitance density with wider capacitance variation over temperature.
• Y5U – Extended high-capacitance dielectric with larger temperature-related variation.

Voltage Characteristics

Applied DC bias influences effective capacitance differently depending on dielectric class.
Higher-permittivity materials typically exhibit more pronounced capacitance change under applied voltage compared to stable dielectrics.

Frequency Characteristics

Frequency response is also dielectric dependent.
Stable dielectrics maintain consistent performance across frequency ranges, while high-capacitance materials may show greater variation.

Material Selection Considerations

• Select NPO when capacitance stability is critical.
• Select X7R for general-purpose filtering and decoupling applications.
• Select Z5U or Y5U when higher capacitance within limited space is required and wider tolerance is acceptable.
• Evaluate operating temperature range before final selection.
• Consider voltage bias effects in DC applications.

Reference Document

Detailed capacitance change characteristics versus temperature, voltage, and frequency are available at:

http://www.suntan.com.hk/pdf/Ceramic-Capacitors/Capacitance.pdf

Contact

For technical inquiries regarding ceramic capacitor selection, please contact:
Email: sales@suntan.com.hk
Email: info@suntan.com.hk