Introduction

Some say charging over wireless is just the latest hype, I would say it is a way of keeping an open mind to the technoligical development.

Alot of phones are beginning to show additions of wireless charging options, while they are becoming more available, there is still the lack of support in the lowend to mid range segment.

This guide is showing how to implement wireless charging on the Samsung Galaxy S4 mini, where the charging pad stays hidden underneath the cover, while keeping NFC, USB port and all other items free to be used.

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    • Disassembling the wireless charging pad, to make it as thin as possible.

    • Inside there is a rubber pad, in order to prevent excessive heat disipating through the back of the charging pad, remove this.

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    • Soldering on thin flexible wires to the + and - on the wireless charging pad

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    • Soldering the wireless charging pad connection + to CN2 on the USB port and - to the ground on the USB port, any part of the external metal surface should work.

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    • Use a small file to make room for the wires on the back frame just below where the battery sits.

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    • Using the USB board replacement guide, step 3 - 8 in reverse order to place the back cover, making sure the wires to the charging pad fits through the ready made holes.

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    • Placing the wireless charging pad, slightly off center to keep NFC, which is implemented in the battery, working.

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    • Samsung Galaxy S4 mini booting after fitting wireless charging pad.

Conclusion

While one would think, soldering a charging coil onto the charging connections would yield in a shortening of the normal connections to the battery, how ever it turns out the combination is very robust.

The phone will charge without issues on a cable connection, aswell as on the wireless charging pad, and data connection via cable remains intact.

By using the charging pad, the coil do get a bit warm, the insulation material removed in step 1, to make it as thin as possible can have an effect on the heat dissepating to the battery from the coil.

Over my usage of this setup I have not yet come across any miss behaviour of the phone due to the charging over wireless or any other issues arisen from this configuration.

Kenneth H. Nielsen

Member since: 04/08/11

449 Reputation

2 comments

I tryed to copy your guide and soldered everything in place (5V to this usb pin & Ground to the usb-port), messed up the charging coil a bit by ripping off the whole connector (I now have only 2 pads left for soldering to) and if i place it on the dock, the flashy lights on the dock will turn on, but the phone will not charge.

As you said normal charging by usb works fine, but i cant figure out my problem.

Jann Bern -

Hi Jann

I have used this approach on three different phones, you need to make sure the + connection on the charging pad is soldered onto the connection on the USB port that is marked by the CN2 arrow on the main board.

I had one that showed the same issues you are describing here, taking the phone apart and resoldering the + connection solved that issue.

Best regards

Kenneth H. Nielsen -