Magnetic Charger

I tried making a magnetic charger using a magnetic charger and breakout boards from Amazon. I plugged it in, but it won’t charge. Please help. anything helps.

What’s on the back of those boards? Are there spots for the CC pins? You need those pins, USB-PD is negotiated using the CC lines. There are 2 CC lines, normal cables only need one, but in an extension like this, if you want the plug to be reversible you should connect both lines.

There are some USB-C boards that do provide the CCs lines, I’ve built custom extension cables with them, but many other boards do not provide the CC pins. Or they put a resistor on one, if so you could remove it.

Yea, the male / green board has a resistor on one of the CC lines. For the female / blue board, I can’t see what that pad is connected to. It might go through a via to the other side of the board. Would need sharper pics of both sides.

If you have at least one CC line, if that pad is CC on the blue board, then you might be able to make it work.

Oh hey, do you have a link to where you brought the boards? Might be sharper pics there.



No pic of the back there.
But found it here

Yea, it looks like one of the CC lines.
On the green board, you’d need to move the resistor then solder a wire to the right side, and connect to the blue board.

There is no resistor on your blue board, correct? I can’t tell for certain. If there is, you’d need to remove that resistor too.

There is no resistor on the D1 of the blue board. Can you explain more on what to do with the green board?

Did you see my post edit, with the picture?
On the green board, there is a small black resistor, that needs to be removed. When resistors are that small you can often just put a blob of solder on it, covering both ends, then slide it off with your soldering iron.

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That’s it. Just remove the black resistor from R2 on the green board? What happens when I do?

Yep. Once it’s removed then that CC line will be free & you can connect it to the CC pad on blue board.

Oh, so transfer the resistor from the R2 pad on the green board to the R1 pad of the blue board? Just want to make sure that I’m getting this correctly.

No. Just remove the resistor.
Then you connect a wire from right side of where the resistor was, that wire needs to go to the free pad on the blue board.

The yellow line here is a wire.

Now, be aware that because you only have one CC line I believe this will only work in one orientation. Like how older USB plugs only fit if right-side up. Your USB-C extender will only work in one orientation, try it one way, if it doesn’t work flip it.

Can you explain how this works please?

The resistor on the green board is a “pull-up” resistor, it’s connected to voltage positive, this is a dumb passive signal and works only for a specific application. But USB-PD is done with an active digital negotiation, the CC line needs to be free in order for it to do that.

What do you mean by pull up resistor? How thick does the wire need to be?

“pull-up” is just a name for what the resistor is doing. It’s a normal resistor. Because it’s connected to voltage positive, it’s called a pull-up. It’s pulling the CC line up. Alternatively, if it was connected to ground / negative, then it would be called a pull-down.

The wire doesn’t have to be thick, it’s just a low current digital signal.

Can the wire be too thin?

I mean, yeah. There is some very fine wire.
But any normal wire that you have will probably be good.

It didn’t work