What is shielded inductor?
Shileded inductor-a type of inductor which is design having a ferrite housing,so that could achieve the effect of isolating, shielding the unstable signal of radio frequency and other nearby electronic components are not affected.
Shielded inductors can be used to suppress electromagnetic interference (EMI) and radio frequency interference (RFI), as well as reduce crosstalk noise. Shielded inductors are usually composed of a coil, a magnetic core, and a shell, where the magnetic core and shell are made of conductive materials and isolated from the coil.
Its structure is similar to that of ordinary inductors, but it has a protective layer such as ferrite or magnetic shielding pads to shield external electromagnetic wave interference and prevent interference signals from propagating into the device through the inductor.
This structure can effectively suppress interference from external EMI signals and prevent noise output from the inductor itself. It can provide good common mode suppression effect, making the device work more stable.
Shield Inductor
Shielded inductors mounted on a PCB – the Inductor is surrounded by the ferrite material
Unshielded Inductor
Non-shielded inductor - magnetic field closes through the surrounding air and can affect any nearby electronic components.
Shielded inductor from the surface can not see the naked coil (shielded inductor is surrounded by the ferrite material) , all the naked coil is unshielded, but the non-naked is not necessarily the shielded inductor, such as ZXcompo Radial inductor,It’s just a thermal expansion casing on the outside.
The working principle of shielding inductance is to limit the interference signal in the reverse direction through the inductive effect of inductance, thereby achieving the purpose of shielding.
Inductance devices can form impedance at high frequencies and produce phase differences in impedance. Due to the impedance change of the inductor itself, the interference signal will encounter greater resistance and thus be shielded.
(★If you want to know more about SMD inductors, you can refer to the following article: • Working Principle And Application Of SMD Inductor)
Shielded inductor with very good shielded, high current rating and low DCR (whole winding is surrounded by the ferrite material)
The main function of the shielded inductor is to suppress the high-frequency noise and EMI signals in the power supply, and provide a clean and stable power supply environment for the subsequent circuits.
Specifically, shielded inductors can play the following roles:
Suppress high-frequency noise
The shielded inductor can suppress the noise in the high-frequency area of the power supply through its own inductance characteristics, thereby reducing the high-frequency noise output by the power supply.
Suppress EMI signals
The magnetic shielding structure of the shielded inductor can effectively suppress the interference of external EMI signals, thereby providing a cleaner and more stable power supply environment.
Specifically, shielded inductors can play the following roles:
Improve system stability
By using shielded inductors, the noise and EMI signals output by the power supply can be effectively reduced, thereby improving the stability and reliability of the system.
Shielded inductors have the following characteristics:
Strong high-frequency suppression capability
Since the shielded inductor adopts a magnetic shielding structure, it has a strong suppression capability in the high-frequency area and can effectively filter out high-frequency noise and EMI signals in the power supply.
Stable inductance value
The coil of the shielded inductor is usually wound with multiple strands, so its inductance value is relatively stable and will not be affected by the external environment.
Compact structure
Shielded inductors usually adopt an integrated structure of magnetic core and shell, which makes its structure compact, small in size, and easy to assemble and install.
In electronic devices, shielded inductors are mainly used to suppress electromagnetic radiation and radio frequency noise.
Common application scenarios include:
Preventing power supply interference: Using shielded inductors on power lines can reduce noise, increase system reliability, and protect equipment from damage by external electromagnetic radiation.
Signal isolation: In the transmission of sound, video or other signals, shielded inductors can be used to isolate electromagnetic interference between transmission lines and signal sources, thereby improving signal quality and stability.
RF interface filtering: Shielded inductors can also be used for filtering RF interfaces, which can suppress interference signals such as noise and echo to ensure RF signal quality.
When selecting and using shielded inductors, you need to pay attention to the following points:
Choose an inductor that matches the circuit requirements: When choosing, you need to consider factors such as the circuit environment, operating frequency, inductance value, current, impedance, etc.
Placement: You need to consider the placement and connection method of the shielded inductor to ensure its correct use in the circuit.
Stability and performance: You need to pay attention to the temperature stability, impedance and other performance indicators of the shielded inductor to ensure its normal operation and enhance the stability of the system.
Environmental adaptability: You need to consider the impact of environmental factors such as vibration, temperature, and humidity on the shielded inductor to ensure the stability and reliability of the equipment in various environments.
In order to improve the performance and reliability of shielded inductors, the following points should be noted:
Maintain reliable electrical connections: The electrical connections of shielded inductors should be stable and reliable, effectively avoiding faults such as poor contact, open circuit, and short circuit.
Reasonable layout and size: The layout and size of shielded inductors should be reasonable to avoid unnecessary magnetic or electric field interference.
Appropriate heat dissipation measures: In high-power applications, proper attention should be paid to heat dissipation to ensure the stability and reliability of shielded inductors under high power consumption.
In conclusion, a shielded inductor is an inductor with a magnetic shielding structure, which is mainly used to suppress high-frequency noise and EMI signals in power supplies. Shielded inductors are increasingly used in electronic devices. How to select and use appropriate shielded inductors and how to improve performance and reliability are issues that designers and engineers need to pay attention to and solve.
Offering a wide range of shielded and unshielded inductors, Zxcompo is a reliable inductor manufacturer to meet your specific needs. Contact us: sales@ZXcompo.com
