The inductance in ordinary electronic circuit is air-core coil or coil with magnetic core, which can only pass small current and bear low voltage; Power inductors also have air-core coils and coils with magnetic cores, which are mainly characterized by being wound with thick wires and can withstand tens, hundreds, thousands or even tens of thousands of amps. Power chip inductors are divided into magnetic and non-magnetic covers, which are mainly composed of magnetic cores and copper wires. It mainly plays the role of filter and vibration in the circuit. So what is the principle and function of patch inductance? The interpretation is as follows.
Principle of patch capacitance
Inductor is the property of closed circuit, that is, when the current changes through the closed circuit, the electromotive force will resist the current change. This inductor is called self-inductor, which is the property of closed circuit itself. Assuming that the current of one closed circuit changes and the electromotive force is in another closed circuit, this inductance is called mutual inductance. When two inductors are close to each other, the change of magnetic field of one inductor will affect the other inductor. This effect is mutual inductance. The mutual inductance depends on the self-inductance of the inductance coil and the combination degree of the two inductance coils, and the components made by this principle are called transformers.
Patch inductance
Chip induction is an electromagnetic induction element of insulated wire winding. It is a common sensing element. Function of chip inductor: It is a simple saying to communicate through DC resistor, which isolates AC signal, and filters, capacitors and resistors constitute resonant circuit. The function of coordination and frequency selective inductor: the inductance coil and capacitor are connected in parallel to form LC coordination circuit. Any current in the circuit of the chip inductor will produce a magnetic field, and the magnetic flux of the magnetic field will also act on the circuit.
When the current passing through the chip inductor changes, the DC voltage potential generated by the chip inductor will prevent the current from changing. When the current of the inductor coil increases and the self-induced electromotive force generated by the inductor coil and the current of the inductor coil decrease, the self-induced electromotive force is in the same direction as the current to prevent the current from decreasing and release the stored energy to compensate for the current decrease. On the contrary, flow prevents current from increasing, and at the same time, it converts part of electric energy into magnetic field, which can be stored in inductance; Therefore, after inductance filtering, not only the ripple of load current and voltage decreases and the waveform becomes smooth, but also the conduction angle of rectifier diode increases.
Shielded chip inductors are different from ordinary chip inductors. Ordinary chip inductors have no shielding in the circuit. When used, the inductor can not achieve the expected effect in the circuit. Shielded inductor can shield the current instability in some circuits and play a good role in blocking. A complete metal shield with shielding inductance surrounds the positive conductor, and the inside of the shield induces the same negative charge of the charged conductor. There is a positive charge equal to the charged conductor on the outside. When the metal shield is grounded, the positive charge on the outside flows into the earth, and there is no electric field on the outside, that is, the electric field with positive electrical conductor is shielded by the metal shield.
Shielding inductance also plays a coupling role in the circuit. In order to reduce the coupling interference voltage of alternating electric field to sensitive circuit, the inductor can set a metal shield with good conductivity between the interference source and sensitive circuit, and ground the metal shield. The coupling interference voltage of alternating electric field to sensitive circuit depends on the accumulation of alternating electric field voltage, coupling capacitance and grounding resistance of metal shield. As long as the metal shield is grounded well, the coupling interference voltage of alternating electric field to sensitive circuit can be reduced. The electric field shielding is mainly reflection, and the thickness of shielding body need not be too large, and the structural strength is the main consideration.
