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Telpherion

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Hello! I've recently piked up a Demon Front single PCB version. I've removed the factory battery to avoid leaking. Anyway I would like to keep the settings and high score save functionality, so I would like to install a coin cell holder on it. I've seen a couple of mod for the regular PGM board with carts, but here the circuit seems to be different. I would like to know how to disable the charging circuit to use a regular CR2032 not rechargeable battery. Thanks! :)
 

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You can still put in a barrier diode just like the normal PGM Mother boards.... OR any battery device anyway.

Use a shokey Silicon diode.

T.
 

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It might work... BUT A NI-MH or NI-Cad have way different charging methods THAN lithium......
 
I've checked up on datasheets for rechargable lithium coin-cell batteries before, but haven't found anything that specifies a special charging circuit is required. It seems that the coin cells are designed to be flexible and charge off any supplied power, whether that charging power is stable or variable (although they charge better on a stable supply of course). They're used in solar-powered chargers, hand-cranked flashlights, etc.

https://www.renata.com/fileadmin/downloads/Flyer/Renata_industry_rechargeable_coin_cells.pdf

They can also be purchased encased in rubber with wire leads coming out if you're worried about the cell rupturing from bad charging.

https://www.digikey.com/product-detail/en/illinois-capacitor/RJD3555HPPV30M/1572-1627-ND/6159145
 
I've checked up on datasheets for rechargable lithium coin-cell batteries before, but haven't found anything that specifies a special charging circuit is required. It seems that the coin cells are designed to be flexible and charge off any supplied power, whether that charging power is stable or variable (although they charge better on a stable supply of course). They're used in solar-powered chargers, hand-cranked flashlights, etc.

https://www.renata.com/fileadmin/downloads/Flyer/Renata_industry_rechargeable_coin_cells.pdf

They can also be purchased encased in rubber with wire leads coming out if you're worried about the cell rupturing from bad charging.

https://www.digikey.com/product-detail/en/illinois-capacitor/RJD3555HPPV30M/1572-1627-ND/6159145
Ok, I was able to find a rechargeable 3,6V coin battery on a local store, so I simply installed the holder and keep the charging circuit. Thanks you all for the replies guys! :)
 

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