4. Type of Applied Voltage and Self-heating Temperature
1.Confirm the operating conditions to make sure that no large current is flowing into the capacitor due to the continuous application of an AC voltage or pulse voltage.
When a DC rated voltage product is used in an AC voltage circuit or a pulse voltage circuit, the AC current or pulse current will flow into the capacitor; therefore check the self-heating condition.
Please confirm the surface temperature of the capacitor so that the temperature remains within the upper limits of the operating temperature, including the rise in temperature due to self-heating.
When the capacitor is used with a high-frequency voltage or pulse voltage, heat may be generated by dielectric loss.
<Applicable to Temperature Characteristic U2J(7U), C0G(5C)>
1-1. Since the self-heating is low in the low loss series, the allowable power becomes extremely high compared to the common X7R(X7R) characteristics.
However, when a load with self-heating of 20 C is applied at the rated voltage, the allowable power may be exceeded. When the capacitor is used in a high-frequency voltage circuit of 1kHz or more,
the frequency of the applied voltage should be less than 500kHz sine wave (less than 100kHz for a product with rated voltage of DC3.15kV), to limit the voltage load so that the load remains
within the derating shown in the following figure. In the case of non-sine wave, high-frequency components exceeding the fundamental frequency may be included. In such a case, please contact Murata.
The excessive generation of heat may cause deterioration of the characteristics and reliability of the capacitor.
(Absolutely do not perform measurements while the cooling fan is operating, as an accurate measurement may not be performed.)
<Applicable to Temperature Characteristic X7R(R7), X7T(D7)>
1-1. The load should be contained so that the self-heating of the capacitor body remains below 20°C, when measuring at an ambient temperature of 25°C. In addition, use a K thermocouple of ø0.1mm
with less heat capacity when measuring, and measure in a condition where there is no effect from the radiant heat of other components or air flow caused by convection. Excessive generation of heat may cause deterioration of
the characteristics and reliability of the capacitor. (Absolutely do not perform measurements while the cooling fan is operating, as an accurate measurement may not be performed.)
The surface temperature of the capacitor : 125°C or less
(including self-heating)
Chip(L×W): 2.0×1.25mm
Chip(L×W): 3.2×1.6mm
Chip(L×W): 3.2×1.6mm
C0G(5C) Char. Rated Voltage:DC250V
C0G(5C) Char. Rated Voltage:DC250V
C0G(5C) Char. RatedꢀVoltage :ꢀDC500V
Frequency VS Allowable Sine Wave Voltage
GCM31A7U2J122JX01-00B
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MURATA [ muRata ]
