Contact Us
TEL: +86-752-7803358
FAX: +86-752-5872218
E-mail: sales@magtop.com
Address: Building A, Pingnan Geumgok Power Ind. Park, Zhongkai  High-tech Zone, Huizhou, Guangdong, China.
Home > Exhibitions > Content
Note on the selection and use of chip inductors
Sep 03, 2018



Note on the selection and use of chip inductors


Note on the selection and application of chip inductor components:


1. Inductance and tolerance


Inductance refers to the nominal value of the inductance of the frequency measurement required by the product specification.


The error is subdivided into: F (±1%); G (±2%); H (±3%); J (±5%); K (±10%); L (±15) %); M grade (±20%); P grade (±25%); N grade (±30%); the most commonly used are J, K, M grades.


2. DC resistance


Except for power inductors that do not measure DC resistance (only check the wire size), other inductors must specify the maximum DC resistance as required, generally as small as possible.


3. Saturation current


Take the 1.25 to 1.5 times of the rated current of the inductor as the maximum operating current. Generally, the derating should be 50%. It is safe to use.


4. Stability of inductance


The ratio of the inductance ΔL/Δt and the original inductance L value of the inductor due to the change of the ambient temperature at 1 °C is the temperature system a1 of the inductor, a1=ΔL/L*Δt. In addition to the temperature coefficient of inductance to determine its stability, attention should also be paid to changes in inductance due to mechanical vibration and ageing.


5. Resistance to electric strength and moisture


For inductors with electrical strength requirements, the type of package material with high withstand voltage should be selected. Generally, the inductor with better withstand voltage has better moisture resistance. Resin impregnation, encapsulation, and die casting processes can meet this requirement.


6. Frequency characteristics of the inductor


At low frequencies, the chip inductor generally exhibits an inductive characteristic, which only functions to store energy and filter high frequencies. However, at high frequencies, its impedance characteristics are very obvious. There are energy consumption and heat, and the inductive effect is reduced. The high frequency characteristics of different inductors are different.


7. Pad or pin


Pads or pins are important directions that can not be ignored when purchasing and using inductors. They mainly evaluate tensile force, torque, solder heat resistance and solderability test to ensure the reliability of soldering.


8. Packaging protection


a, the magnetic material of the inductor is fragile, and care should be taken during handling and storage;


b. Packaging of the product: Generally, the small box is used as the inner packaging, and the outer packaging is selected as a solid double-layer cardboard box, which can withstand a maximum pressure of 40Kg.





What should you pay attention to during the use of chip inductors?


1. When the chip inductor is used, the humidity and dryness, the ambient temperature, the high frequency or low frequency environment, the inductance should be expressed, or the impedance characteristics, etc., should pay attention.


2, the variation of the inductance caused by the ambient temperature change of 1 °C of the chip inductor ΔL / Δt and the value of the original inductance L value of the inductance of the temperature system a1, a1 = △ L / L * Δt. In addition to the temperature coefficient of inductance to determine its stability, attention should also be paid to changes in inductance due to mechanical vibration and ageing.


3. At low frequencies, the chip inductor generally exhibits an inductive characteristic, which only functions to store energy and filter high frequencies. However, at high frequencies, its impedance characteristics are very obvious. There are energy consumption and heat, and the inductive effect is reduced. The high frequency characteristics of different inductors are different.


4, the chip inductor design to withstand the large current, and the corresponding heat.


5, pay attention to the wire (enamel wire, yarn package or bare wire), commonly used enameled wire. To find the most suitable line.


6, the pad or pin is an important direction to buy and use the inductor coil can not be ignored, mainly to assess its tensile force, torque, welding heat and solderability test, etc., to ensure the reliability of welding. For the chip inductor (SMD) must be strictly in accordance with the design of the pad size, with the inductance of the pin, generally not strictly specified the same parameters and vertical, horizontal interchangeable, only due to PC board installation position restrictions and specified varieties .


7, rated current is the maximum current value allowed by the chip inductor during normal operation. When the inductor is in use, the current flowing cannot exceed the rated current. Otherwise, the inductor will change its performance parameters due to heat generation, and even burn out due to overcurrent.


Previous: Chip inductor saturation current and rated current resolution?

Next: How much is the electromagnetic radiation of the inductor?