Then you need a MOSFET where the Rds(on) = E/I = 0.150/2
...from scratch, or just use available modules?
The "1A" specification of the lower module image that you posted, is not the output current limit. It's the regulated charging current.
not scratch, just use the circuit from the module and same parts. as i need that protection in my circuit board.
see those 2 links, even though they are using same parts, the OC is different.
See reply #43
ohh, i think we better discuss after the test.
Sounds wise. When you come back with results, please give exhaustive details about the procedure. You tend to release vital information in tiny little tidbits, turning the thread into a "game of 100 questions".
Right, so let's actually READ the information available on them on their respective eBay listings. Here's from the narrow strip-like module:
Then have a look at the other one:
Eerily similar, eh? Funny, the way the sellers actually give information about their products.
Now let's see what we know about that 8205 dual N-MOS. It says its RDSon is somewhere around 25~40mR depending on Vgs, but curves aren't provided in the datasheet.
Still, if we take the 3A overcurrent protection rating from one of the sellers (it's close to 2.8A anyway, right?), that would imply 0.15V / 3A = 50mR. Geee...that's funny, since if you put two halves of a 8205 in series, then that would break down into 2x 25mR. Funny that, since that's the RDSon given for Vgs=4.5V and probably its minimum RDSon value.
How about the competing product that 'only' rates at 2.8A? that would imply RDSon of ca. 54mR, or 27mR per device. Maybe the additional 2mR are due to trace lengths - or maybe the people who rated their product at 2.8A actually measured it, and the competitor just stuck to the 8205 datasheet and called it a day.
Either way, the whole mystery isn't so much a mystery if one actually READS the information provided by the seller, and SHARES critical information with others if they want the puzzle to be solved. 
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... reply #2 
Not just that...turns out the eBay ads contain crucial information that is not in line with what @rahmanshaber kept pressing, i.e. that both products in fact have more or less the same spec w.r.t. overcurrent protection. That information was only available once the eBay links were posted. And again, if OP had actually read the links he posted himself, hoe would have had a straight answer all along...
I tested them both, funny as it is both allowed 1.8amp way over what i need.
@anon35827816 thanks for the insights. yes, i should have read them carefully. I tested the tp4056 module before and it wasn't allowing over 1 amp. I am definitely sure about it. that's why i am saying one only allowed 1 amp. that was a year ago. this 2 module i brought it recently. maybe they are genuine parts, that old one was a copy?
Nevertheless i got to issue solved. thanks @anon57585045 and @anon35827816.
Hi,
What part numbers on your ICs on the board?
Full part number.
Tom... 
PS. Sorry but your reply had no part numbers in it.
dw0a1 and 8205A
1 amp of what? See, herein lies the problem. You don't specify, and perhaps don't understand, the specific metric. Did you measure charge current, or discharge current? Continuous or peak? More importantly, note that the current could also be limited on the side of the power supply (e.g. a usb port, but also any smps will have overcurrent protection) or even on the battery side (if it is a pack that has integrated overcurrent protection circuitry).
Likely none of the products you evaluated was "fake", but you simply were a little nonchalant in evaluating them.
In any case, for your custom pcb, I think you should have a decent idea now of how to approach it. I don't see a reason not to use this particular IC, combined with the apparently popular dual mosfet or a different mosfet of your choice.
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