SMT inductance principle - and functions
SMT inductance principle is introduced and effect in this paper, the principle of SMT inductance effect, probably about 970 words in this paper, to read the full article 10 minutes.
SMT inductance principle is introduced: the inductance is an attribute of a closed loop, namely when by closed loop of current change, there will be a electromotive force to resist the change of the current.
The inductance is called self-induction is closed loop attributes of their own.
Suppose a closed loop current change, produced by induction electromotive force in another closed loop, the inductance is called mutual induction.
Two inductance coil near each other, an inductance coil magnetic field changes will affect another inductor, this influence is mutual inductance.
Mutual inductance depends on the size of the two inductance coil inductance coil self-induction and the degree of coupling, using the principle of component is called a transformer.
SMT inductance: the role SMT inductance is to use wire winding insulation and electromagnetic induction element.
Belong to common inductance components.
SMT inductance: the effect of dc resistance communication this is simple, the ac signal isolation, filtering, or with the capacitor, resistor to form a resonance circuit.
Tuning and frequency selective inductance: the effect of inductor and capacitor in parallel can be composed of LC circuit.
Any current in SMT inductance in the circuit can produce a magnetic field, the magnetic flux of the magnetic field ACTS on the circuit.
When the SMT inductance current through changes, SMT inductance of dc voltage is set to prevent the change of the current.
When through the inductor current increases, and the self-induced electromotive force produced by inductance coil electricity through the inductor current, small self induction electromotive force and the current in the same direction, to stop the decrease of the current, release the stored energy at the same time, to compensate for the decrease of the current.
Flow direction on the contrary, stop the current increase, at the same time, will be part of the electrical energy is converted into the magnetic field can be stored in inductance;
So after inductance filter, not only the pulse load current and the voltage is reduced, the waveform is smooth, and rectifier diode conduction Angle 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, which are positively charged conductor of the electric field shielding in the metal mask.
Shield inductance in the circuit also have the effect of the coupling, shielding SMT inductance to reduce the coupling disturbance voltage of alternating electric field on sensitive circuit inductance can be set between the source and the sensitive circuit conductive metal shield, and the metal shield grounding.
Alternating electric field coupling interference voltage depends on the sensitive circuit voltage alternating electric field, the coupling capacitance and metal shield grounding resistance of the product.
As long as to try to make the metal shield good grounding, it can make the alternating electric field on sensitive circuit coupling interference voltage is small.
Electric field shielding is given priority to with reflection, so don't get the thickness of the shield is too large, and the structural strength as the main factor.
HTML this paper label: inductors SMD inductance SMD inductance principle is introduced and the function in the previous: capacitor structure classification in the next article: small inductance knowledge