Question Charge and Play Circuit

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Hey guys! I have designed a regulator PCB board for the Wii:




It works great and is actually quite small at just 24.6 x 20.5 mm and I used SOT-23-5 chips so it would be easier to solder than QFN since my attempt at the PowerMii Lite was a failure...



Anyway, back to the point. I'm looking to improve my board.



I have added some charging management ICs but charge and play is not supported.



I want to do something like this:
https://bitbuilt.net/forums/index.php?threads/easy-charge-and-play-circuit.1417/

But on an SMD scale to keep the size small. Unfortunately I'm a bit lost on how this circuit works exactly.



It looks like all I need is an SMD size P-Channel MOSFET, an SMD Schottky diode, an SMD 100K resistor and possibly a small size inductor too. There are just so many options on Digi-Key and I feel lost...



Any idea how I can make this happen?
 

Gman

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I would start by finding the characteristics of the recommended components and then try searching for the closest match in SMD size taking into consideration max current, resistance, size, etc.. You can narrow down the searches on digikey by entering the parameters.

Have you seen my wii reg board? It does custom regulators, play/charge, and more. https://bitbuilt.net/forums/index.php?threads/wii-power-management-system-open-source.2607/
It is much easier assembling QFN chips using a solder stencil, solder paste, and hot air.
 
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I would start by finding the characteristics of the recommended components and then try searching for the closest match in SMD size taking into consideration max current, resistance, size, etc.. You can narrow down the searches on digikey by entering the parameters.

Have you seen my wii reg board? It does custom regulators, play/charge, and more. https://bitbuilt.net/forums/index.php?threads/wii-power-management-system-open-source.2607/
It is much easier assembling QFN chips using a solder stencil, solder paste, and hot air.
Yes I have actually, beautiful work! You're board is everything I would need and more, however I am trying to challenge myself and build my own circuit just for the joy of it.

That's what I decided to do was just compare the specs of an SMD version of the components based off that guide.

Technically, the wii to play and charge would need at most maybe 3.5A, so an SMD MOSFET that can handle 8A and a Schottky Diode that can handle 5A should be fine right?

Thank you for your response!
 

Gman

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Yes I have actually, beautiful work! You're board is everything I would need and more, however I am trying to challenge myself and build my own circuit just for the joy of it.

That's what I decided to do was just compare the specs of an SMD version of the components based off that guide.

Technically, the wii to play and charge would need at most maybe 3.5A, so an SMD MOSFET that can handle 8A and a Schottky Diode that can handle 5A should be fine right?

Thank you for your response!
Keep in mind you can't charge the batteries with a DC source directly, it needs a current profile for proper li-ion charging safety. You will also need a charging circuit like the red board (which already does play/charge built in)
 
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Keep in mind you can't charge the batteries with a DC source directly, it needs a current profile for proper li-ion charging safety. You will also need a charging circuit like the red board (which already does play/charge built in)
Haha, yes of course! I’m fully aware of battery safety and protection boards and all, but thank you for the reminder. The red board would be great however I believe it only works for 7.4V 2S battery packs and I’m looking for a 1S2P setup, like your custom board, but preferably I personally would like to design it and have fabricated. Thank you for your help Gman!
 
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