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5. DC Voltage and AC Voltage Characteristic
1. The capacitance value of a high dielectric constant type
capacitor changes depending on the DC voltage applied.
Please consider the DC voltage characteristics when a
capacitor is selected for use in a DC circuit.
1-1. The capacitance of ceramic capacitors may change
sharply depending on the applied voltage. (See figure)
Please confirm the following in order to secure the
capacitance.
(1) Determine whether the capacitance change caused
by the applied voltage is within the allowed range .
(2) In the DC voltage characteristics, the rate of
capacitance change becomes larger as voltage
increases, even if the applied voltage is below
the rated voltage. When a high dielectric constant
type capacitor is used in a circuit that requires a
tight (narrow) capacitance tolerance (e.g., a time
constant circuit), please carefully consider the
voltage characteristics, and confirm the various
characteristics in the actual operating conditions
of the system.
2. The capacitance values of high dielectric
constant type capacitors changes depending
on the AC voltage applied.
Please consider the AC voltage characteristics
when selecting a capacitor to be used in a
AC circuit.
6. Capacitance Aging
1. The high dielectric constant type capacitors
have an Aging characteristic in which the capacitance
value decreases with the passage of time.
When you use a high dielectric constant type
capacitors in a circuit that needs a tight (narrow)
capacitance tolerance (e.g., a time-constant circuit),
please carefully consider the characteristics
of these capacitors, such as their aging, voltage,
and temperature characteristics. In addition,
check capacitors using your actual appliances
at the intended environment and operating conditions.
7.Vibration and Shock
1. Please confirm the kind of vibration and/or shock, its condition, and any generation of resonance.
Please mount the capacitor so as not to generate resonance, and do not allow any impact on the terminals.
2. Mechanical shock due to being dropped may cause damage or
a crack in the dielectric material of the capacitor.
Do not use a dropped capacitor because the quality and reliability
may be deteriorated.
3. When printed circuit boards are piled up or handled, the corner
of another printed circuit board
should not be allowed to hit the capacitor in order to avoid
a crack or other damage to the capacitor.
JEMCGC-2703M
[Example of DC Voltage Characteristics]
Sample: X7R(R7) Characteristics
20
0
-20
-40
-60
-80
-100
0
10
[Example of AC Voltage Characteristics]
Sample: X7R(R7) Characteristics
30
20
10
0
-10
-20
-30
-40
-50
-60
0
0.5
[ Example of Change Over Time (Aging characteristics) ]
20
10
0
-10
-20
-30
-40
10
100
11
0.1μF, Rated Voltage 50VDC
20
30
40
DC Voltage (V)
10μF, Rated Voltage 6.3VDC
1
1.5
AC Voltage (Vr.m.s.)
C0G(5C)
X7R(R7)
X5R(R6)
1000
Time(h)
Crack
Floor
Mounting printed circuit board
Crack
Caution
!
50
2
10000
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