While tp4056 based circuits are widely available and super cheap (less than 0.5 USD including shipping), tp4057 circuits are rare and about 8 times more expensive.
Do you know where can I get a cheap tp4057 based circuit (about 1 USD)?
A budget tp4057 based charging circuit
Sun, 05/02/2021 - 17:10
#1
A budget tp4057 based charging circuit
Edited by: FearOfTheDark on 05/02/2021 - 17:10
What benefit does it have over the 4056?
Reverse polarity protection
I have seen several of these circuits for 2$ US on Aliexpress. still more than 50¢ but available.
While reverse polarity protection is a nice features, these boards are often soldered into arduino projects, hobby tools and RC, et al. They could have lithium cells that are a more permanent part of the setup (non removable, or with special connectors) or the entire cell is difficult to reverse.
But I do understand the need for the feature on other circuits.
The Cheapest I Can find on Aliexperss is 4.31 including shipping
It is for a project including a removable 18650 so I do need the reverse polarity protection
https://s.click.aliexpress.com/e/_9zTTp5
https://s.click.aliexpress.com/e/_AKz7Lh
10 for 11 dollars, 6 after coupons if you have any.
If you are a new user, click on https://a.aliexpress.com/_mri2XNp to get coupons.
Are you sure the 4057 has battery side reverse polarity protection? I can’t read Chinese but it seems quite rare and expensive when filtering for chips with battery side reverse polarity protection on Digikey that I resorted to looking for an alternative method such as a resettable ptc fuse. Power supply side reverse polarity protection is common, battery side is not.
Yeah, it’s kind of assumed the cell is going to be soldered-in, correctly, like for a powerbank or other doodad, and not be removable.
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
Google translate says “Adopt SOT23 package 500㎡A anti-reverse connection charger for lithium battery” so I think it has reverse polarity protection
Yes but the tp4056 also has anti reverse/reverse polarity protection but that’s at the power source only, not battery side rpp.