SMD Type-High Voltage
Multi Layer Ceramic Capacitors
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18
Application(Typical circuit)
DC-DC Converter
Switching Power Supply
Caution(Rating)
1. Operating Voltage
When DC-rated capacitors are to be used in AC or ripple current circuits, be sure to maintain the Vp-p Value of the
applied voltage or the Vo-p which contains DC bias within the rated voltage range.
When the voltage is applied to the circuit, starting or stopping may generate irregular voltage for a transit period
because of resonance or switching. Be sure to use a capacitor with a rated voltage range that includes these
irregular voltages.
Voltage
DV Voltage
DC+AC Voltage
AC Voltage
Pulse Voltage(1)
Pulse Voltage(2)
Positional
Measurement
C2 : X7R ; 250V 10nF~47nF
C3 : COG ; 630V 47pF~100pF
C3 : COG, X7R ; 2kV 100pF~1000pF
C4 : COG, X7R ; 2kV 100pF~1000pF
2. Test condition for AC withstanding Voltage
Primary circuit and Snubber switching power supply
(1) Test Equipment
Tests for AC withstanding voltage should be made with equipment capable of creating a wave similar to a 50/60
Hz sine wave. If the distorted sine wave or overload exceeding the specified voltage value is applied, a defect
may be caused.
(2) Voltage applied method
The capacitor's leads or terminals should be firmly connected to the output of the withstanding voltage test
equipment, and then the voltage should be raised from near zero to the test voltage. If the test voltage is applied
C1, C2 : COG or X7R 1000pF~4700pF
C4
: COG ; 2kV 100pF~330pF
C5
: COG ; 1kV/2kV 100pF~470pF
directly to the capacitor without raising it from near zero,it should be applied with the
*zero cross.
At the end of the test time, the test voltage should be reduced to near
zero, and then the capacitor's leads or terminals should be taken off the output of the
withstanding voltage test equipment. If the test voltage is applied directly to the
capacitor without raising it from near zero, surge voltage may occur and cause a
defect.
*ZERO CROSS
is the point where voltage sine wave
(3) Dielectric strength testing method
LCD back light Inverter
In case of dielectric strength test, the capacitor’s is applied between the terminations for 1 to 5 sec., provided the
charge/discharge current is less than 50mA.
3. Soldering
C2 : COG ; 3kV 10 ~100pF
If a chip component is heated or cooled abruptly during soldering, it may crack due to the thermal shock. To
prevent this, follow our recommendations below for adequate soldering conditions. Carefully perform preheating
so that temperature difference (ΔT) between the
solder and component surface is in the following
range. The smaller the temperatures difference (Δ
T)
between the solder and component surface is,
the smaller the influence on the chip is.
Chip Size
Slodering Method
Reflow Method or
Soldering Lron Method
3.2×1.6mm
and under
ΔT
190℃
3.2×2.5mm
and over
ΔT
130℃
SAMWHA CAPACITOR Co., Ltd.
Multi Layer Ceramic Capacitors
19
SAMWHA [ SAMWHA ELECTRIC ]
