SAMSUNG ELECTRO-MECHANICS

SAMSUNG MLCC Capacitance Change & Effect on a SET [1] Capacitance change [2] Effect on a SET

SAMSUNG 1. Capacitance change, MLCC characterisitcs Capacitance is influenced by the conditions shown below (1~4) [MLCC Internal structure] MLCC characteristics - Tolerance / Effect - Capacitance change MLCC characteristics - Temperature Coefficient(TCC) / Effect - Capacitance change MLCC characteristics - Aging / Effect - Capacitance reduction MLCC characteristics - DC-Bias, AC Voltage / Effect - Capacitance change MLCC characteristics - Rated Voltage / Effect - Maximum applicable voltage MLCC characteristics - Breakdown Voltage (BDV) / Effect - Insulation breakdown Voltage MLCC characteristics - Insulation Resistance (IR) / Effect - LEakage current MLCC characteristics - Dissipation Factor (DF) / Effect - Self heating (∝ESR), Q-Factor MLCC characteristics - Ripple current / Effect - Self heating (∝ESR) MLCC characteristics - Operating Frequency / Effect - Impedance (Z) & ESR

SAMSUNG 1. Capacitance change, TCC, Aging Capacitance decreases in over time & high temp. conditions 2. TCC TCC - / Cap. Change - / Temp. Range - TCC - Y5V / Cap. Change - -82%~+22% / Temp. Range - -30℃~+85℃ TCC - X5R / Cap. Change - ±15% / Temp. Range - -55℃~+85℃ TCC - X7R / Cap. Change - ±15% / Temp. Range - -55℃~+125℃ 3. Aging Ct=C0(1-klog10t) Ct = Capacitance value, t hours after the start of aging C0 = Initial capacitance value, k=Aing constant, t=Aging time ※ Capacitance will recover its capacity while soldering

SAMSUNG 1. Capacitance change, DC Bias & AC Voltage Capacitance is changed by applied voltage conditions 4. DC Bias Spontaneous Polarization of Dipole ※ Dipoles are aligned in the direction of the Electric field > Decrease the polarization change rate in the ac field 4. AC Voltage Movement of Domain-Wall ※ Increase the applied AC voltage to the MLCC > Increase the polarization change rate in the AC field

SAMSUNG 1. Capacitance change, Real example Margin design is required to consider the characteristics MLCC(X5R) ex) 3225m, 10uF, 50V, Tol. 10% ※ The above value is one of the sample data of general MLCCs ※ Please refer to the specific datasheet when you design

SAMSUNG 2. Effect on a SET, Signal Line Capacitance change should be considered when designing [Low-pass filter (Noise suppression)] Raw Siginal > LPF > High Capacitance OK, Low Capacitance Fail [Using as a time constant] Charging time for triggering ※ Using X5R/X7R is recommended for time constant circuit

SAMSUNG 2. Effect on a SET, Power converter regulating Lower capacitance leads bigger output voltage ripple # Simulation conditions > Topology: Buck, Frequency: 3MHz, Vin: 4V, Vout: 1V, Duty ration = 25% Capacitance - 1uF / Vout Ripple - 12mV Capacitance - 3.2uF / Vout Ripple - 2.5mV Capacitance - 10uF / Vout Ripple - 1.2mV

SAMSUNG 2. Effect on a SET, Decoupling It affects input voltage ripple, which can be a reason of malfunction [Decoupling Circuit & Impedance] [Decoupling Cap. Impedance(Z)] Vac=Iac*Z ※ Voltage ripple is proportional to "Impedance of decoupling cap."