Main parameters of resistors and capacitors - News - Global IC Trade Starts Here Free Products

SMD aluminum electrolytic capacitor

Brand AVX TPSE226M035R0125 Low impedance tantalum capacitor AVX 22

Chip ceramic capacitor

Tantalum capacitor

The main electrical parameters of the resistor are as follows:
1) Nominal resistance and tolerance:
2) Rated power:
3) Maximum working voltage:
4) Noise electromotive force:
5) Temperature coefficient:
The main characteristic parameters of the capacitor:
(1) Capacity and error: The maximum deviation range allowed by the actual capacitance and the nominal capacitance. Generally divided into 3 levels: I grade ± 5%, grade II ± 10%, grade III ± 20%. In some cases, there is a level 0 with an error of ±20%.
Precision capacitors have smaller tolerances, while electrolytic capacitors have larger errors and they use different levels of error.
Commonly used capacitors have the same level of accuracy as resistors. Expressed by letter: D - 005 - ± 0.5%; F - 01 - ± 1%; G - 02 - ± 2%; J - I - ± 5%; K - - Class II - ± 10%; M - Class III - ± 20%.
(2) Rated working voltage: The capacitor can work stably and reliably for a long time in the circuit, and the maximum DC voltage it bears is also called withstand voltage. For devices with the same structure, medium and capacity, the higher the withstand voltage, the larger the volume.
(3) Temperature coefficient: The relative change value of the capacitance for every 1 °C change in temperature within a certain temperature range. The smaller the temperature coefficient, the better.
(4) Insulation resistance: used to indicate the size of the leakage. Generally, a small-capacity capacitor has a large insulation resistance of several hundred megaohms or several gigaohms. The insulation resistance of electrolytic capacitors is generally small. Relatively speaking, the larger the insulation resistance, the better the leakage is.
(5) Loss: The energy consumed by a capacitor to generate heat per unit time under the action of an electric field. These losses are mainly due to dielectric loss and metal loss. Usually expressed by the loss tangent value.
(6) Frequency characteristics: The nature of the electrical parameters of the capacitor as a function of the frequency of the electric field. In a capacitor operating under high frequency conditions, since the dielectric constant is smaller at a high frequency than at a low frequency, the capacitance is also reduced accordingly. Losses also increase with increasing frequency. In addition, when operating at high frequencies, the distribution parameters of the capacitor, such as the resistance of the pole piece, the resistance between the lead and the pole piece, the inductance of the pole piece, the inductance of the lead, etc., all affect the performance of the capacitor. All of this limits the frequency of use of the capacitor.
Different types of capacitors have different maximum frequency of use. The small mica capacitor is within 250MHZ; the wafer type ceramic capacitor is 300MHZ; the round tube type ceramic capacitor is 200MHZ; the disc type ceramic medium is up to 3000MHZ; the small paper capacitor is 80MHZ; the medium paper capacitor is only 8MHZ.
Aluminum electrolytic capacitors
1. DC electrolytic capacitors can only be used on DC circuits. The polarity must be marked in the appropriate position or next to the pin/terminal.
2. If the polarity of the line is not clear or unclear in the circuit loop, it is recommended to use a non-polar electrolytic container.
3. The working environment temperature of the electrolytic capacitor cannot exceed the specified operating temperature range.
4. The electrolytic capacitor should be stored in a low temperature and dry place. If the storage period is long, it should be re-applied with the rated voltage before use.
5. The ripple current through the electrolytic capacitor should not exceed its allowable range. If it exceeds the specified value, an electrolytic capacitor resistant to large ripple current should be selected.
6. When used, the working voltage of the electrolytic capacitor should not exceed its rated voltage.
7. The high-temperature heating device such as electric soldering iron should be kept at an appropriate distance from the plastic casing of the electrolytic capacitor to prevent the plastic casing from rupturing due to overheating.
8. When welding electrolytic capacitors, the welding time and welding temperature should not exceed 10 seconds and 260 degrees Celsius.
9. If the guide pin and terminal are applied more than the specified force, the internal structure of the electrolytic capacitor will be destroyed.