The practical application of multilayer inductors and the four main points of attention

Multilayer inductors are non-wound inductors. The commonly used sizes are 0402, 0805, 0603, 1206, 1210, 1812, etc. The multilayer inductors have good magnetic shielding, high sintering density, and good mechanical strength. They are comparable to wire-wound inductors. Compared with the small size, it is conducive to the miniaturization of the circuit, the magnetic circuit is closed, it will not interfere with the surrounding components, and will not be interfered by the surrounding components, which is conducive to the high-density installation of the components;

Laminated integrated structure, high reliability, good heat resistance, good solderability, regular shape, suitable for automated surface mounting production. The disadvantage is that the pass rate is low, the cost is high, the inductance is small, and the Q value is small.

At present, laminated inductors are widely used in notebook computer digital TV, digital video recorder, list player, hard disk drive, personal computer and other general consumer and computer main products input and output line noise elimination fields. In the actual application of inductors, unexpected phenomena sometimes occur. After sorting out and summarizing, pay special attention to the following four points:

1. The temperature is too high

It is normal for the inductor to generate heat during the working process, leading to an increase in temperature. If the temperature is too high, the temperature of the iron core and the coil will easily rise and lead to changes in inductance.

Therefore, it is necessary to pay attention to the working environment temperature of the inductor and to select an inductor with appropriate specifications.

2. Magnetic field interference

When the inductor is working, an electromagnetic field is generated around it due to the flow of current. Place other components as far away as possible from the inductor or at right angles to the inductor to reduce interference. To reduce interference. If the requirement is higher, an inductor with a shield can be used instead.

3. Contact resistance

In the middle of the magnetic coil of each layer of the inductor, the capacity will be spread, which can lead to double-loop power supply for high-frequency data signals, reducing the actual filtering effect of the inductor. Therefore, it is necessary to pay attention when using the inductor to carry out high-frequency filtering.

4. Inductance measurement

When measuring the inductance value and Q value with the instrument, the test lead should be as close as possible to the inductor to ensure the accuracy of the data.