不同种类电容特性比较

Decoupling Back up
Logic loop
~75%
Impedance & ESR considered more important than capacitance
High Frequency loop Power loop
Major used around Digital IC to filter Noise
Electrical →Mechanical
Mother Board Resonated With MLCC
・Big Sound (Like Speaker)
SRF of MLCC Become Lower
Sound Effect of MLCC
Phenomenon Analysis
Understanding
D/D converter input
No Bias
D/D converter output
OS-CON
Aluminum solid capacitors with organic semi-conductive electrolyte
Features of OS-CON 1. OS-CON is a low ESR capacitor 2. ESR of OS-CON is not dependent on temperature 3. OS-CON has long-life 4. OS-CON is a capacitor that has polarity but that is strong
INTRODUCTION
元誠科技股份有限公司
Yuan Cheng Technology Co. , Ltd By Oliver Chen
GENERAL POPULAR CAPACITOR
Multi-layer Ceramic Capacitor OS-CON Capacitor Aluminum Electrolytic Capacitor Tantalum Solid Electrolytic Capacitor Specialty Polymer Capacitor Polymer Organic Semi-conductive Capacitor Film Capacitor
against reverse voltage 5. High conductivity provides stability against temperature
because has low resistance value compared to other electrolytes.
FREQUENCY(KHZ)
X7R 1206 2.2UF/16V
FREQUENCY(KHZ)
X7R 1206 3.3UF/10V
FREQUENCY(KHZ)
FREQUENCY(KHZ)
ESR Characteristics of Frequency
Temperature Characteristics of Capacitance
(MLCC)
• ・Dielectric Constant of Material • ・DC Bias Voltage • ・Frequency Range • ・Layout of Mother Board
Mechanism of Sound Effect
(MLCC)
V
Time
・Piezo Electric with DC-Bias ・Vibration of MLCC With AC Current
Qualitative Analysis
Mechanism of Vibration ( Simulation )
Quantitative Analysis
Vibration - Sound Analysis
Solution for
Piezo Effect
|z| xc
About MLCC Impedance Features XL
ESR (mΩ) ESL (πH)
Multilayer ceramic capacitors
Tantalum electrolytic capacitors
Aluminum electrolytic capacitors
5 ~ 30 1 ~ 2 300 ~ 1000 2 ~ 6 500 ~ 10000 4 ~ 10
3.if the working frequency > SRF, |Z| dominated by XL
Typical ESR and ESL factors in capacitor ( 100K ~ 10MHz ) Impedance = R 2 + ( 2πf L – 1/2πf c) 2
＊ Values of Tantalum electrolytic capacitor may vary depending on case size
Capacitance Characteristics of Frequency
X7R 1206 1UF/16V
X7R 1206 1.5UF/16V
Audio loop Other loop
~25%
Smoothing Filter Resonant Coupling
Must consider temperature characteristics and capacitance on design
Factor of Sound Mechanism
ESR SRF
Frequency SRF:SBiblioteka Baiduries Resonance Frequency
SRF→ fc=1/2π LC |Z|= ESR2+(XC-XL)2
1.if the working frequency = SRF ,XC-XL=0, |Z|=ESR
2.if the working frequency < SRF, |Z| dominated by Xc
Multi-layer Ceramic Capacitor
Separate the system loop and the capacitors used
Loop separated
Capacitor Functions
Digital loop Analog loop combined ratio