1. Do You Know Something About EQ Bobbin?? ? ? Type of EQ bobbin is generally used in production of high power inductor and transformer with the requirement of assembly space, which is matched with EQ type magnetic core. The transformer is mainly composed of bobbin, core, enameled wire, insulating tape (paper), etc., in which the bobbin plays a supporting role and the iron core acts as a bridge for energy conversion. And the enameled wire is mainly used for windings, and insulating tape is used to guarantee the insulation between windings. It is generally called vertical bobbin, which is similar to PQ bobbin and matched with the core of bigger Ae value. In magnetic cores, the magnetic flux density can be calculated by using effective area Ae. It is used to satisfy the products of the requirement with high power. The EQ bobbin is selected to make the switch power transformers, pulse transformers and electronic ballasts, etc. It is widely applied in household appliances, lighting, communications, medical equipment and other fields. TAKE EQ2514 BOBBIN AS AN EXAMPLE:
1. Do You Know Something About EQ Bobbin?
Type of EQ bobbin is generally used in production of high power inductor and transformer with the requirement of assembly space, which is matched with EQ type magnetic core. The transformer is mainly composed of bobbin, core, enameled wire, insulating tape (paper), etc., in which the bobbin plays a supporting role and the iron core acts as a bridge for energy conversion. And the enameled wire is mainly used for windings, and insulating tape is used to guarantee the insulation between windings. It is generally called vertical bobbin, which is similar to PQ bobbin and matched with the core of bigger Ae value. In magnetic cores, the magnetic flux density can be calculated by using effective area Ae. It is used to satisfy the products of the requirement with high power. The EQ bobbin is selected to make the switch power transformers, pulse transformers and electronic ballasts, etc. It is widely applied in household appliances, lighting, communications, medical equipment and other fields.
TAKE EQ2514 BOBBIN AS AN EXAMPLE:
(1) PIN NO. : 5:5P
(2) PIN PITCH: 5.0
(3) ROW PITCH: 22.7
(4) PIN DIAMETER: φ0.7
THE FOLLOWING IS A DATA TABLE ABOUT ALL THE SPECIFICATIONS OF EQ BOBBIN THAT PROVIDED BY OUR FACTORY.
2. The Function of Noise Filter in Power Supply Equipment
The power supply of electronic equipment, such as 220V/50Hz AC network or 115V/400Hz AC generator, has various EMI noises. The man-made EMI jamming sources, such as radio emission signals of radar, navigation and communication equipment, can induce EMI signals on the power supply line and the connecting cable of electronic equipment, and rotate electronically. Mechanical and ignition systems will produce transient process and radiated noise interference in inductive load circuits, as well as natural interference sources, transformer bobbin, transformer bobbin design, transformer bobbin ee16, transformer bobbin sizes chart, such as lightning discharges and space electrical interference noise in the universe. The former has a short duration but a large energy, while the latter has a wide frequency range. In addition, thermal noise will also occur when the electronic circuit components themselves work. These electromagnetic interference noises, coupled by radiation and transmission, will affect the normal operation of various electronic devices operating in this environment.
On the other hand, electronic equipment will produce various kinds of electromagnetic interference noise when working. For example, the digital circuit uses the pulse signal (square wave) to represent the logical relationship. The Fourier series analysis of its pulse waveform shows that its harmonic spectrum range is very wide. In addition, there are a variety of complex frequency pulses in digital circuits. These pulses contain more abundant harmonics, wider spectrum and more complex electromagnetic interference noise.
Various kinds of regulated power supply itself is also a kind of electromagnetic interference source. In linear regulated circuit, the unidirectional pulse current formed by rectification can also cause electromagnetic interference. Switched power supply has the advantages of small size and high efficiency. It is more and more widely used in modern electronic equipment, but because it is in the switching state during power conversion, it is very important in itself. Strong BMI noise source produces EMI noise with a wide frequency range and high intensity. These electromagnetic interferences also pollute the electromagnetic environment by radiation and transmission, affecting the normal work of other electronic devices.
For electronic equipment, when EMI noise affects the analog circuit, the signal-to-noise ratio of the signal transmission will deteriorate, and when it is serious, the signal to be transmitted will be submerged by EMI noise and can not be processed. When the EMI noise affects the digital circuit, it will cause the error of logic relation and result in the wrong result.
For power supply equipment, besides power conversion circuit, there are driving circuit, control circuit, protection circuit, input and output level detection circuit, etc. These circuits are mainly composed of general purpose or special purpose integrated circuits. When the power supply stops working due to electromagnetic interference, the electronic equipment can not work normally. Do. The use of power network noise filter can effectively prevent power supply from misoperation due to external electromagnetic noise interference.
3. Selection of Ferrite Materials
Various ferrite materials have different characteristics according to their composition and specific manufacturing process, so they are suitable for different occasions.
In LC filters, the quality factor of the core coil. Relating to the μQ product of ferrite core material, we must select the ferrite core material with the highest Q product in this frequency band according to the frequency band of the filter.
MnZn ferrite materials are suitable for low and intermediate frequencies. When we make the filter inductor coil which is required by the common characteristic of low frequency operation, transformer bobbin suppliers, transformer bobbins and cores, transformer bobbin material, we can choose the material with the initial permeability of 10002000 ordinary manganese-zinc ferrite. If the characteristics of low-frequency filters are required to be high or miniaturized, the Mn-Zn ferrites with high μ and high Q characteristics in the initial permeability range mentioned above can be selected, and the product of μQ should be hundreds of thousands.
The medium frequency Mn-Zn ferrite material with initial permeability of about 600 is suitable for making inductance coils of IF filters. The performance of this material is much better than that of the material mentioned before when it is used in intermediate frequency.
If the variable is made, then the high μ low Q Mn-Zn ferrite material should be selected. Its initial permeability is generally at the right of 2000. This material is often made into an air-gap-free core.
Linear zinc ferrite materials have the characteristics of low and high Q. The initial permeability of the materials is generally about 40-100. Zinc ferrite materials are suitable for high frequency applications. If the filter works at high frequency, the core made of nickel-zinc ferrite material should be selected to make the core coil.
4. What Are The Connections And Differences between Inductance And Magnetic Beads
1). Inductance is an energy storage element, and magnetic beads are energy conversion (consumption) devices.
2). Inductors are mostly used in power filter circuit, magnetic beads are mostly used in signal circuit and EMC countermeasures.
3). Magnetic beads are mainly used to suppress electromagnetic radiation interference, while inductors are mainly used to suppress conductive interference. Both of them can be used to deal with EMC and EMI problems. There are two ways of EMI, radiation and transmission. Different ways have different suppression methods. The former uses magnetic beads and the latter uses inductance.
4). Magnetic beads are used to absorb ultra-high frequency signals, such as some RF circuits, PLL, transformer bobbin size, transformer bobbin types, oscillation circuits, including ultra-high frequency memory circuits (DDR SDRAM, RAMBUS, etc.) all need to add magnetic beads in the input part of the power supply. Inductance is a kind of energy storage element, which is used in LC oscillation circuits, medium and low frequency filter circuits, and its application frequency range is rarely more than 50 MHZ.
5). Inductance is generally used in circuit matching and signal quality control. General connection and power connection. Use magnetic beads where they are combined analogically and digitally. Magnetic beads are also used for signal lines.
The size of the magnetic beads (which should be the characteristic curve of the beads) depends on the frequency of the interference waves that need to be absorbed by the beads. Magnetic beads are high frequency resistance, low resistance to DC and high resistance to high frequency. For example, 1000R@100Mhz means 1000Ω resistance to 100Mhz frequency signal. Because the unit of magnetic beads is nominated according to the impedance it produces at a certain frequency, the unit of impedance is also ohm. Characteristic curves of frequency and impedance are usually attached to the data sheet of magnetic beads. Generally, the standard is 100MHz, such as 2012 B601, which means that the Impedance of magnetic beads is 600 ohms at 100MHz.
5. Why Does The Temperature Characteristic of The Magnetic Permeability of The Magnetic Ring Used in The Energy-saving Lamp Pulse-driven Transformer Require A Negative Temperature Coefficient?
Generally, the decrease of inductance of pulse transformer means that its side induced current decreases, the base dynamic current of triode decreases, and the collector current decreases, which is negative temperature coefficient. When the temperature of the transistor increases, the current amplification coefficient increases and the collector current increases. Generally, when the working temperature of the transistor rises from room temperature to 100 C, the current amplification coefficient will increase by about 10%~15%, which is a positive temperature coefficient. Therefore, with the increase of ambient temperature, the negative temperature coefficient of magnetic ring and the positive temperature coefficient of transistor cancel each other or partially offset the influence of current in the working process of energy-saving lamp, which can make the energy-saving lamp work steadily and is extremely beneficial to solve and improve the problem of temperature rise of energy-saving lamp. In this temperature range, if the temperature characteristic of the magnetic permeability of the magnetic ring used in the pulse-driven transformer is also a positive temperature coefficient, it will form a vicious superposition with the positive temperature coefficient of the transistor current gain, transformer bobbin catalogue, transformer bobbin and core, which will greatly increase the current of the energy-saving lamps and may lead to the working power of the lamps exceeding the design upper limit. This situation is more serious in the environment of high temperature, and there are greater security risks.
That is to say, if the inductance of the magnetic ring of the pulse-driven transformer is from room temperature to 100 C, it should have a certain negative temperature coefficient, which is offset by the positive temperature coefficient of the current gain of the crystal switch tube, thus greatly stabilizing the working current and power of the lamp, so that the power of the lamp tube in the whole temperature range of different regions and seasons is within the design range.