Information

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Design and specifi cations are subject to change without notice. Ask factory for technical specifi cations before purchase and/or use.
Whenever a doubt about safety arises from this product, please contact us immediately for technical consultation.
Gold Capacitors Technical Guide
Operating Techniques of Gold Capacitors
Expected life
The expected life is calculated as follows:
Expected life = Guaranteed life x Temperature factor x Voltage factor
= 1000(h) x 22.6 x 1.1 = 24800(h) = 2.8years
The back-up time is about 38 hours.
Humidity factor
The life-time of Gold Capacitors is largely dependent on humidity. If a Gold Capacitor is to be used in high humidity
conditions, please contact your local technical representative for assistance.
These calculation results are for reference only. They are not guaranteed values.
Please carefully review your design parameters prior to implementation.
4-2 Notes on using Electric Double Layer Capacitors
4-2-1 Notice
1. Life-time
Gold capacitors have a longer life than secondary batteries, although limited. During use, capacitance decreases
and internal resistance increases. Taking into consideration suffi cient back-up time when designing the circuit, the
life-time of a Gold Capacitor is greatly affected by ambient temperature, applied voltage and operating currents. By
reducing these factors as much as possible, capacitor life-time can be lengthened. Using products beyond life-
time may change characteristics rapidly, and may cause a short-circuit, trigger the pressure relief vent, or cause the
electrolyte to leak.
2.Residual electric charge
Since Gold capacitors can hold a substantial charge, there may be residual electric charge built up that could
damage other low-withstanding voltage parts such as semiconductors.
3.Ambient temperature and humidity
• Capacitor life is affected by operating temperature. In general, lowering ambient temperature by 10°C will
double the life of a capacitor. Use the capacitor at the lowest possible temperature within the maximum operating
temperature.
• Operation above the specifi ed maximum temperature not only shortens capacitor life, but also causes serious
damage such as electrolyte leakage. Verify the operating temperature of the capacitor by taking into consideration
not only the ambient and internal temperature, but also thernal radiation from heat generating elements inside the
unit (power transistor, IC’s, resistors, etc.) and self-heating due to ripple currents. Be careful not to place heat-
generating elements across from the capacitor on the opposite side of the PCB.
• Capacitor life is affected by ambient humidity. Product life is considerably shortened when using Gold capacitors
in the high humidity conditions.
4.Voltage drop during back-up operation
Take careful note of the voltage drop caused by the instantaneous operating current and the internal resistance of
the Gold Capacitor when switching from power - failure - detection to back-up mode. Because internal resistance
varies by product, use the following table to decide the correct operating (discharge) current.
Series
Maximum operating (discharge) Current
0.047F 0.1 to 0.33F 0.47 to 1.5F 3.3 to 4.7F 10F to 50F
SG, SD, SE, NF
200
µA 300µA
1mA
−−
F
200
µA 300µA 300µA −−
EL
− 300µA
1mA
−−
EN
− 10µA −−−
HW
−−
100mA 300mA 1A