1, LC circuit is an oscillation circuit composed of inductors and capacitors, and its oscillation principle is based on the exchange of energy between inductors and capacitors. In LC circuit, when there is charge on capacitor, it will generate electric field and store electrical energy; Inductors convert electrical energy into magnetic energy. When the charge on the capacitor flows through the inductor, the magnetic energy is converted back into electrical energy and stored in the capacitor.
2, RC oscillator circuit is composed of resistance R and capacitor C is suitable for generating low-frequency signal circuit. RC oscillation circuit, using RC frequency selection network, suitable for low-frequency oscillation, generally used to generate 1Hz~As shown in the attached picture.
This is a wireless mic circuit: the audio signal generated by the mic is amplified by BG1 and added to the base of BG2 as a modulated signal. The capacitor three-point oscillator circuit is composed of BG2, C4, L, C5 and R5. The resulting radio frequency sends the signal out. The working principle of the oscillating circuit is: once the circuit is powered on, the power supply charges the C3 through R4. The base voltage of BG2 does not rise, and the collector voltage does not fall.
In LC circuits, inductors and capacitors can act as impedances individually or together. When inductors and capacitorsWhen acting together, they produce complementary effects in frequency, resulting in a periodic curve of high and low impedance regions called the LC filter. One of the important uses of LC circuits is in oscillating circuits.
The oscillation stage uses the "Colpitts" oscillation circuit, although it is also LC oscillation, but this LC is not that LC, can not be confused with the stability of other FM circuits, a hand touch or people near the point of running frequency that is not a thing. Oscillation is done by a 2SC1907 tube, COILA and the 10PF above it and on the leftDetermines the basic frequency of the circuit.
Hello "L" inductance is oscillating and cannot be replaced by resistance. If it is used as a transmitter, it is possible, but its transmission power is very small. External audio input is fine, but you need to change the circuit.
The oscillating current is a kind of current that changes in size and direction with the period, and the circuit that can generate the oscillating current is called the oscillating circuit. The simplest of these is called the LC circuit.
InductanceThe resonant frequency of L1 and capacitor C1 is 1MHz, and because the circuit is resonant, the no-load current is small when the receiving coil is not near the transmitting coil. The receiving end also adopts the mode of resonance, which can maximize the transmission efficiency of energy, and the direct current is obtained by the filtered capacitor after the Schottky diode is rectified, and the charging current is above 0.6A. If the coil is made into a barrel shape, the transmission efficiency will be higher.
Wireless charging coil A6 three 3 coil - inductance 15uH. Inductance basic formula and inductance definition formula: L=μ×Ae*N2/l. , whichMedium: L indicates inductance, μ indicates the magnetic permeability of the magnetic core, Ae indicates the cross-sectional area of the magnetic core, N indicates the number of turns of the coil, lm indicates the magnetic circuit length of the magnetic core. Empirical formula: L= (k*μ0*μs*N2*S) /l. Among them. μ0 is the vacuum permeability =4π*10 (-7).
Wireless charging technology uses magnetic resonance to transmit electrical energy in the electric and magnetic fields between the charger and the device, and the coil and capacitor form a resonance between the charger and the device. The system could be used in a wide range of future applications, such as charging zones for electric vehicles and power transmission for computer chips. adoptThe charging system developed by this technology would require only one hundred and fifty times of the current charging time.
Wireless charging system mainly adopts the principle of electromagnetic induction, energy coupling through the coil to achieve energy transfer. When the system works, the input end converts the AC mains into direct current through the full bridge rectifier circuit, or uses the 24V direct current end to supply power to the system directly. After passing through the power management module, the output direct current is converted into high-frequency alternating current through the 2M active crystal oscillator inverter to supply the primary winding.
Wireless charging technology has a long history, and for ordinary consumers, wireless charging looks very magicalThe basic principle of wireless charging is that the current is converted into a magnetic field, and the magnetic field is transmitted through the air and then converted into a current to be transmitted to the intelligent terminal. After charging the battery and passing through the power management module, the DC output is converted into high-frequency alternating current through the 2M active crystal oscillator inverter to supply the primary winding.1, wireless charging Wireless charging lc oscillation The way is electromagnetic induction, magnetic resonance, electric field couplingType and radio wave transmission and other methods wireless charging lc oscillation , mobile phone wireless charging lc oscillation Wireless charging mostly uses the principle of electromagnetic induction. Electromagnetic induction wireless charging, when the current of the power supply through the coil (wireless charger's power supply coil) will generate a magnetic field, its wireless charging lc oscillation his unenergized coil (mobile phone side of the electric coil) close to the magnetic field will generate current, charging the mobile phone. As shown below.
2, wireless charging is also known as induction chargingElectric or non-contact inductive charging, based on the principle of electromagnetic induction, does not need to transmit electricity to the device like the traditional wired charger, but the device that needs to be charged can be charged by contacting the wireless charging base. 3, wireless charging is also known as inductive charging, non-contact inductive charging, from wireless power transmission technology, is the use of near-field induction, that is, inductive coupling, by the power supply device (charger) to transmit energy to the power device, the device uses the received energy to charge the battery, and at the same time for its own operation.
4, the principle of wireless charging technology is"In simple terms, the charging device and two pieces of "magnetic equipment" installed on the mobile phone device are induced to each other and form a current. At present, products supporting wireless charging have appeared in mobile phones, electric vehicles, smart furniture and other fields. Among them, in the mobile phone industry, the "Qi standard" is the most common, and Qi labels are often used in the packaging of many mobile phones and wireless chargers.
5, mobile phone wireless charging technology is completely without the use of wires, the use of magnets for mobile phone charging technology. Mobile phone wireless charging technology, derived from wireless power transmission technology, uses magnetic resonance between the charger and the phoneThe electric charge is transferred in the air, and the coil and capacitor form a resonance between the charger and the mobile phone, realizing the technology of efficient transmission of electric energy.
6, the specific principle is that both ends of the wireless charging device can generate the same frequency magnetic field through the resonator to achieve the purpose of resonance generation of electric energy for mobile phone charging. From the point of view of the charging principle, in addition to the advantages of longer wireless transmission distance, there are also the advantages of convenient manufacturing of equipment. Only because this wireless charging efficiency is relatively poor, it is gradually replaced by other wireless charging methods in the mobile phone market.
Wireless charging source is installed inside a electromagnetic coil, after the power switch is turned on, the electromagnetic coil converts the power supply battery into a large amount of magnetic energy, and then uses a reverse coil (international standard brick QI coil) to receive this large amount of magnetic energy, convert it into electrical energy, through a metal output head, into our equipment reserve battery. Wireless charging Because electromagnetic transmission only needs to be transmitted in space, no medium is required, so wireless charging can be carried out.
Wireless charging methods include electromagnetic induction, magnetic resonance, and electricityField coupling and radio wave transmission, wireless charging of mobile phones mostly uses the principle of electromagnetic induction. Electromagnetic induction wireless charging, when the current of the power supply through the coil (wireless charger's power supply coil) will generate a magnetic field, other unenergized coil (mobile phone side of the electric coil) close to the magnetic field will generate current, charging the mobile phone. As shown below.
Wireless charging system mainly adopts the principle of electromagnetic induction. Wireless charger refers to the charger that does not need to be connected to the terminal device that needs to be charged without the traditional charging power cord, and uses the latest wireless charging technology by using the magnetic field generated between the coilsIn order to transfer power, inductive coupling technology will become a bridge connecting charging base stations and equipment.
Electromagnetic induction type primary coil A certain frequency of alternating current, through electromagnetic induction in the secondary coil to produce a certain current, thereby transferring energy from the transmission end to the receiving end.
It is the first generation of mobile phone wireless charging, and the technology is mature, but it can only be single-to-single short-range charging (qi standard, within 1cm, within 5 watts), rather than single-to-multiple charging like WiFi.
The reason why the wireless charging circuit should use LC output is as follows: The charging method of the wireless charger is to use the induced magnetic flux generated between the wireless charging board and the induction magnet on the mobile phone, and convert this magnetic force into a power for current transmission.
A device charged by electromagnetic wave induction, similar to a transformer.
Slow charging speed: Due to the current mobile phone and other receiving devices, most limit the input power, so the charging speed is slow. High cost: electronic circuits with push coils are required in chargers, and in receiving devicesTo have an electronic device for power conversion, both need to have coils, and high-frequency filtering circuits are required to meet electromagnetic compatibility, so the cost is higher than direct charging.
Wireless charging system mainly uses the principle of electromagnetic induction, energy coupling through the coil to achieve energy transfer. After passing through the power management module, the output direct current is converted into high-frequency alternating current through the 2M active crystal oscillator inverter to supply the primary winding. By coupling the energy of the two inductors, the electrical output of the secondary coil is changed into direct current through the receiving conversion circuit to charge the battery.