The function and principle of SMT inductor

In general, the inductance of an electronic circuit is a hollow coil, or a coil with a magnetic core.And the power inductor also has the hollow coil, also has the magnetic core, the main characteristic is with the thick wire winding system, can withstand tens of amperes, hundreds of thousands, even tens of thousands of amperes.

The power SMT inductor is divided into two types: magnetic housing and without housing, mainly composed of magnetic core and copper wire.It mainly plays a filtering and oscillating role in the circuit.

Introduction to SMD inductance principle:

Inductance is a property of a closed loop that when the current through the closed loop changes, an electromotive force occurs to resist the change in the current.This inductance is called self-inductance and is the property of the closed loop itself.If the current in one closed loop changes and an electromotive force is induced in another closed loop, the inductance is called mutual inductance.

When two inductance coils are close to each other, changes in the magnetic field of one inductance coil will affect the other inductance coil. This effect is mutual inductance.The size of the mutual inductance depends on the degree of coupling between the inductance coil and the two inductance coils.

SMD inductance function:

The SMD inductor is an electromagnetic induction element made by winding an insulated wire.It is a common inductance element.The function of SMD inductor: dc resistance ac this is a simple way of saying that the ac signal isolation, filtering or with capacitors, resistors and other resonant circuit.Functions of tuning and frequency-selecting inductors: an LC tuning circuit can be formed by connecting an inductor coil in parallel with a capacitor.Any current in the SMT inductor generates a magnetic field, the magnetic flux of which ACTS on the circuit.

When the current through the SMT inductor changes, the dc voltage generated in the SMT inductor will prevent the current from changing.When the current through the inductance coil increases, the self-inductive electromotive force generated by the inductance coil is the same as the current when the current through the inductance coil decreases.Flow in the opposite direction, to prevent the increase of the current, at the same time to convert part of the electrical energy into magnetic field energy stored in the inductor;Therefore, after inductance filtering, not only the pulsation of load current and voltage decreases, the waveform becomes smooth, but also the conduction Angle of rectifier diode increases.

SMD inductor with general SMD inductance shielding, average patch of inductance in the circuit is not to bring a mask, use up in the circuit inductance don't want to, the effect of shielding SMT inductance can block out some of the current in the circuit is not stability, good have the effect of blocking, shielding inductive complete metal shield will positively charged conductor surrounded by at the inner side of the shield will be induced with a charged conductor equal amounts of negative charge, the outer appearance and charged conductor of the same amount of positive charge, if the metal shield grounding, the outside of the positive charge will flow into the earth, the lateral electric field will not exist,That is, the electric field with a positive conductor is shielded in a metal shield.

The shielding inductance also plays a coupling role in the circuit. To reduce the coupling interference voltage of the alternating electric field to the sensitive circuit, the shielding inductance can set a metal shield with good conductivity between the interference source and the sensitive circuit, and grounding the metal shield.The coupling interference voltage of ac field to sensitive circuit depends on the product of ac field voltage, coupling capacitance and grounding resistance of metal shield.As long as the metal shield is well grounded, the coupling interference voltage of the ac field to the sensitive circuit can be minimized.Electric field shielding is mainly reflection, so the thickness of shielding body need not be too large, but the structural strength is the main factor.