Engineering Draft CE-AAMX-CEM-1
Application Guidelines 28
1. Circuit Design
1.1 Operating Temperature and Frequency
Electrical parameters for electrolytic capacitors are normally specified at 20 ℃ temperature and 120 Hz frequency.
These parameters vary with changes in temperature and frequency. Circuit designers should take these changes into consideration.
(1) Effects of operating temperature on electrical parameters
a) At higher temperatures, leakage current and capacitance increase while equivalent series resistance (ESR) decreases.
b) At lower temperatures, leakage current and capacitance decrease while equivalent series resistance (ESR) increases.
(2) Effects of frequency on electrical parameters
a) At higher frequencies, capacitance and impedance decrease while tanδ increases.
b) At lower frequencies, heat generated by ripple current will rise due to an increase in equivalent series resistance (ESR).
1.2 Operating Temperature and Life Expectancy
(1) Expected life is affected by operating temperature. Generally, each 10 ℃ reduction in temperature will double the expected life.
Use capacitors at the lowest possible temperature below the upper category temperature.
(2) If operating temperatures exceed the upper category limit, rapid deterioration of electrical parameter will occur and irreversible damage
will result.
Check for the maximum capacitor operating temperatures including ambient temperature, internal capacitor temperature rise due to
ripple current, and the effects of radiated heat from power transistors, IC's or resistors.
Avoid placing components, which could conduct heat to the capacitor from the back side of the circuit board.
(3) The formula for calculating expected life at lower operating temperatures is as follows ;
T
1
-T
2
10
L
2
=L
1
x2
L
1 : Guaranteed life (h) at temperature, T1 ℃
L
2 : Expected life (h) at temperature, T2 ℃
T
1 : Upper category temperature (℃)
T
2 : Actual operating temperature, ambient temperature + temperature rise due to ripple current heating(℃)
(4) Please use according to the lifetime as noted in this specification. Using products beyond end of the lifetime may change characteristics rapidly,
short-circuit, operate pressure relief vent, or leak electrolyte.
Panasonic Electronic Devices Co.,Ltd.
* This specification guarantees the quality and performance of the product as individual components.
Before use, check and evaluate their compatibility with installed in your products.
* Do not use the products beyond the specifications described in this document.
* Install the following systems for a failsafe design to ensure safety if these products are to be used in equipment where a defect in these
products may cause the loss of human life or other signification damage, such as damage to vehicles (automobile, train, vessel), traffic
lights, medical equipment, aerospace equipment, electric heating appliances, combustion/ gas equipment, rotating equipment, and
disaster/crime prevention equipment.
・The system is equipped with a protection circuit and protection device.
・The system is equipped with a redundant circuit or other system to prevent an unsafe status in the event of a single fault.
* Before using the products, carefully check the effects on their quality and performance, and determined whether or not they can be used.
These products are designed and manufactured for general-purpose and standard use in general electronic equipment.
These products are not intended for use in the following special conditions.
1. In liquid, such as Water, Oil, Chemicals, or Organic solvent
2. In direct sunlight, outdoors, or in dust
3. In vapor, such as dew condensation water of resistive element, or water leakage, salty air, or air with a high concentration corrosive
gas, such as Cl2, H2S, NH3, SO2, or NO2
4. In an environment where strong static electricity or electromagnetic waves exist
5. Mounting or placing heat-generating components or inflammables, such as vinyl-coated wires, near these products
6. Sealing or coating of these products or a printed circuit board on which these products are mounted, with resin and other material
7. Using resolvent, water or water-soluble cleaner for flux cleaning agent after soldering.
(In particular, when using water or a water-soluble cleaning agent, be careful not to leave water residues)
* Please arrange circuit design for preventing impulse or transitional voltage.
Do not apply voltage, which exceeds the full rated voltage when the capacitors receive impulse voltage, instantaneous high voltage,
high pulse voltage etc.
* Electrolyte is used in the products. Therefore, misuse can result in rapid deterioration of characteristics and functions of each product.
Electrolyte leakage damages printed circuit and affects performance, characteristics, and functions of customer system.