Circuit design for wireless charger that runs on 10~7V input range

[Sujith Zis]

I needed help designing a wireless charging circuit for a mobile phone using about 7~10V input .....


I'm using stored energy from 2*5.4V super capacitors connected in series


I also need a step down switching regulator circuit to convert the output from super caps in series. to 7~10V range so that it can be used as input for wireless charger

 

[Audioguru]

On the other website I thought you are charging the phone when its high frequency receiving coil is almost touching the high power transmitting coil.
but now I think you want to transmit the charging power wirelessly across the street or across a city.
Haven't you considered the very high losses and the very low amount of power from two super-caps?

 

[Sujith Zis]

On the other website I thought you are charging the phone when its high frequency receiving coil is almost touching the high power transmitting coil.
but now I think you want to transmit the charging power wirelessly across the street or across a city.
Haven't you considered the very high losses and the very low amount of power from two super-caps?

No .. you have got it all wrong .... I'm actually making a peizoelectricity based shoe which gives input to a belt which has the circuitry and storage areas and



I want the wireless mobile charger for I think only like 2cm distant charging

Input upto10v and I think mobile phones require about 3.7 v
So we still have 6V to spare

 

[Audioguru]

A mobile phone has a charger circuit inside that needs a 5V input to charge the lithium battery.
A capacitor charged to +10V discharges to +5V very quickly. A battery charged to +5V discharges to about 4V very slowly. A huge difference.

As I said on the other website, energy harvesting using 23 piezo films in series in a shoe is used to power a low current LCD watch, not to charge a powerful cell phone battery, unless you walk and run VERY FAR for a long time.