Now everyone uses a new way of charging mobile phones, that is wireless charging. So what is the principle of this wireless charger? Wireless charging methods include electromagnetic induction, magnetic resonance, electric field coupling and radio wave transmission, etc. Wireless charging of mobile phones mostly uses the principle of electromagnetic induction.
A changing magnetic field will produce a changing electric field, a changing electric field will produce a changing magnetic field, and its size is related to their rate of change, and the rate of change of the sine function is another sine function, so the electromagnetic wave can spread outThe generation of induced voltage is related to the change of magnetic flux, so the changing magnetic field inside the coil generates induced voltage, thus completing the charging process.
One of the self-wound coil is connected in the charging circuit, 555 output pin (third pin) is connected to an output tube (oneself at will, but to the high-frequency power tube) the output tube is linked to the self-wound coil, and the connected two coils are close (about 1 cm or so there is a very sufficient charging current). The efficiency of this circuit is very low, because there is only half a wave peak high frequency so the loss is relatively large, but the principle is quite simple and easy to produce.