Class 1 and Class 2 MLCCs
- 1. Class 1 and Class 2 MLCCs Testing and Design Considerations December 2017
- 2. Outline • MLCC Construction • Capacitance Stability • Temperature • Voltage • Time • Piezoelectricity and Electrostriction • Parasitics • Effective Series Resistance (ESR) • Effective Series Inductance (ESL) • Ripple Current • KEMET Tools
- 3. C = Design Capacitance K = Dielectric Constant A = Overlap Area d = Ceramic Thickness n = Number of Electrodes Ceramic Capacitor Structure Class 1 and Class 2 + - Capacitances in parallel are additive CT=C1+C2+C3+….Cn
- 4. Dielectric Technology C0G PME & BME 200oC U2J BME X8R BME X8L BME X7R PME & BME 175oC X5R BME Y5V BME Z5U BME BP PME C0G @ Rated V BX PME X7R +15/25% @ Rated V BR PME X7R & +15/- 40% @ Rated V Commercial & Automotive Grade Dielectric Materials Military & Hi-Rel Dielectric Materials Class 1 Class 2 Class 3 Class 1 Class 2
- 6. Temperature Stability (TCC) Temperature CapacitanceShift(%) 25C-55C 125C 0% -15% 85C -50% -1.5% TCC= Temperature Coefficient of Capacitance
- 7. Alpha Symbol Significant Figure of Temp Coefficient ppm/ºC Numerical Symbol Multiplier to significant figure Alpha Symbol Tolerance of Temp Coefficient ± ppm/ºC C 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 -10000 L 500 P 1.5 5 +1 M 1000 R 2.2 6 +10 N 2500 S 3.3 7 +100 T 4.7 8 +1000 U 7.5 9 +10000 Temperature Stability (TCC) Dielectric Classification (Class 1) Temperature Range: -55ºC to +125ºC C0G provides highest temperature stability
- 8. Temperature Stability (TCC) Dielectric Classification (Class 2 and 3) * Industry Classification (Non EIA-198) Alpha Symbol Low Temperature (ºC) Numerical Symbol High Temperature (ºC) Alpha Symbol Max cap change over temp. range (%) Z +10 2 +45 A ±1.0 Y -30 4 +65 B ±1.5 X -55 5 +85 C ±2.2 6 +105 D ±3.3 7 +125 E ±4.7 8 +150 F ±7.5 9 +200 P ±10 R ±15 S ±22 * L +15 to - 40 T +22 to - 33 U +22 to - 56 V +22 to - 82 CLASSIIICLASSII
- 9. Temperature Stability (TCC) C0G Temperature ‘K’Magnitude X7R X5R Z5U Y5V ‘Room’ Ambient U2J Class 3 Class 2 Class 1
- 10. -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 0 4 8 12 16 20 Capchange(%) DC Voltage (V) Capacitance verus DC Voltage X7R 1206 10uF 16V Capacitance Stability Versus DC Voltage – Class 2 and Class 3 VDC
- 11. Capacitance Stability Versus DC Voltage – Class 2 and Class 3 VDC -60% -50% -40% -30% -20% -10% 0% 10% 0 1 2 3 4 5 6 CapacitanceChange Applied DC Bias (VDC) Capacitance Change vs. DC Bias Rated 6.3V 1210 0805 1210 vs 0805, X7R, 10uF, 6.3V
- 12. Capacitance Stability Versus DC Voltage – Class 2 and Class 3 BaTiO3 above 130oC • Cubic • No dipole BaTiO3 below 130oC • Tetragonal • Creates dipole Face Centered Cubic Crystal Structure - + VDC Dipole
- 13. +V -VDomains - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + - + 10V DC Capacitance Stability Versus DC Voltage – Class 2 and Class 3 -90 -80 -70 -60 -50 -40 -30 -20 -10 0 10 0 4 8 12 16 20 Capchange(%) DC Voltage (V) Capacitance verus DC Voltage X7R 1206 10uF 16V VDC
- 14. -10.0% -5.0% 0.0% 5.0% 10.0% 0 0.5 1 1.5 2 2.5 3 Capchange(%) AC Voltage (Vrms) Capacitance versusAC Voltage X7R 1206 10uF 16V Capacitance Stability Versus AC Voltage – Class 2 and Class 3 VAC Measurement Conditions Capacitance Frequency Voltage (AC) ≤10uF 1kHz 1Vrms >10uF 120Hz 0.5Vrms
- 15. Capacitance Measurements of Class 2 Capacitance out of Spec???? Capacitance out of Specification!!!! Instrument Calibrated AC Voltage 1Vrms Frequency 1kHz Example: 1210 10uF 10% Tolerance VAC
- 16. Capacitance Measurements of Class 2 Danger Zone: >1uF VAC Measurement frequency switches from 1kHz to 120Hz
- 17. Capacitance Measurements of Class 2 ALC Function (Auto Leveling Control) Example: 1210 10uF 10% Tolerance Within Specification!!!! VAC
- 18. -20% -10% 0% 10% 20% 0 4 8 12 16 20 Capchange(%) DC Voltage (V) Capacitance Change vs DC Voltage C0G 1210 220nF 25V -10.0% -5.0% 0.0% 5.0% 10.0% 0 0.5 1 1.5 2 2.5 3 Capchange(%) AC Voltage (Vrms) Capacitance Change vs AC Bias C0G 1210 220nF 25V Class 1 MLCCs Ultra Stable versus Voltage No change with DC voltage No change with AC voltage DC Voltage AC Voltage
- 19. 6.00 7.00 8.00 9.00 10.00 11.00 12.00 13.00 14.00 1 10 100 1,000 10,000 100,000 Capacitance(uF) Hours from Last Heat Capacitance vs Time (Aging) Class 2 X7R10uF Nom Lower Limit Upper Limit Capacitance Stability Versus Time (Aging) Class 2 Soldering Process 0Hr https://ec.kemet.com/design-tools/aging-calculator-for-ceramics
- 20. 0.05 0.06 0.07 0.08 0.09 0.10 0.11 0.12 0.13 0.14 0.15 1 10 100 1,000 10,000 100,000 Capacitance(uF) Hours from Last Heat Capacitance vs Time (Aging) Class 1 C0G/U2J 0.1uF Nom Lower Limit Upper Limit Capacitance Stability Versus Time (Aging) Class 1 No change with Time
- 22. Piezoelectricity and Electrostriction - - - - - - + + + + + + - + - + - + Mechanical Distortion
- 24. Electrostriction Audible Noise Audible Noise AC Voltage Low Noise>>
- 25. MLCC Parasitics ESR and ESL
- 26. Real Capacitor Real Capacitor • Nominal capacitance • ESR - Series resistance (terminations, dielectric, and electrodes) • ESL - Series inductance Series Resonance (SRF) where XC = XL Simplified Real Model 10pF example ESR
- 27. 0.001 0.01 0.1 1 10 100 1000 1.0E+02 1.0E+03 1.0E+04 1.0E+05 1.0E+06 1.0E+07 1.0E+08 Impedance/ESR(Ohms) Frequency (Hz) ESR Class 2 X7R versus Class 1 C0G Class 1 ESR(Ohms) Class 2 ESR(Ohms) Real Capacitor Type Typical 100kHz ESR Class 1 C0G 650 mOhms Class 2 X7R 11.4 mOhms
- 28. 0 10 20 30 40 50 60 70 80 90 100 0.1 1.0 10.0 TemperatureRise(C) Ripple Current (Arms) Temperature Rise vs Ripple Current Class 2 X7R versus Class 1 C0G C0G Temperature Rise X7R Temperature Rise Real Capacitor Safe Zone Caution Zone Danger Zone Type Power Dissipation @ 1Arms Class 1 C0G 13.1mW Class 2 X7R 747mW
- 29. Summarizing Class 1, 2, and 3 Property Class 1 Class 2 Class 3 Applications Timing, tuning, pulse, high current, resonators Decoupling, bypass, filtering, transient voltage suppression Limited temperature decoupling, bypass Volumetric Efficiency Temperature Stability Voltage Stability Dissipation Factor and ESR Ripple Current Very Good OK Bad
- 30. KEMET’s K-SIM Impedance and ESR Capacitance loss with DC Bias Ripple Current Spice Model ksim.KEMET.com
- 31. Thank You!!! Mark R. Laps Technical Product Manager Ceramic Business Unit KEMET Electronics Cell Phone: +1-864-399-4879 Office Phone: +1-864-963-6383 www.kemet.com | marklaps@kemet.com