Hi, i am trying to build a protection circuit with DW01, i need 2 amp over-current protection. But i this chip have different variants of it. I can't figure out which one is the correct one for my specification.
Also is there a better chip to do this? I want protection and charging.
Thanks
This chip won't regulate current by itself. It only has protection in case a rogue charger is connected to it. When it does that, it measures the voltage across the MOSFETs which behave more or less like a low valued resistor when they're on. It's spec'd at 150mV nominal. So the current overload trip point depends on the characteristics of your FET in your circuit.
The complete charge circuit you describe would just have a current source and maybe voltage sensor, in line before the DW1.
https://www.roboelements.com/product/1s-2a-bms-li-ion-battery-protection-board-with-nickel-strip/
this one rated for 2A with single mosfet, this chip is DW01 with little dor on top of 0 ,1 and A.
TP4056 module with protection buy Kiev Odessa Kharkov Ukraine
this module's protection part also uses one mosfet but rated for 1A. this DW01A chip, with out any marking on top of the letters.
Both mosfet are same, and uses single mosfet. Only difference i see is in the name of the DW01 chip. you can look at page 4 of the datasheet for this markings.
I tested the 2nd one and it cuts the output at 1A. not tested the 2nd one, but it's rated for 2A.
Not sure if the resistor and caps are same in the both module.
That chip not only protects from overcurrent, also from many other damages.
Also here i concern that chip is cutting the output power line when the discharge current is over 1A or 2A.
I don't know which of this chip variant works on which range, that i want to know.
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I told you, it's not the chip that determines the range. That is why it's not mentioned in the data sheet.
@anon57585045 Please see the #3 comment. both modules are using same mosfet but one is set for 3A and other one 2A.
Can you please explain that?
Hi,
This may help;
Have you Googled;
choosing dw01 battery protection IC
Tom... 
@TomGeorge thanks for sharing. nice video. but it does not explain my question how 2 same module have different OC protection.
I think that r2 resistor is the key. using different values ranging from 1k to 2k gives different overcurrent protection?
@anon57585045 is that it?
Also i tried to messure that resistor in the 2 module i have, and both are 1k. still makes no sense.
Hi,
What are the markings on each of your ICs?
Tom..
@TomGeorge like this.
No. I told you before. The MOSFET is the key. If you don't believe me, go ahead and try.
both module uses same mosfet 8205a but one can handle 1A and other 2A. how that possible?
Measured by you? Where do those numbers come from? Also if you have those modules, you can test your resistor theory (or at least possibly invalidate it), by checking the resistor values.
It's possible that the resistor is the upper part of a voltage divider internal to the DW01, but it's not clear on the internal diagram in the data sheet. But the text contradicts that idea, because it says that the protection is engaged by a 150mV between GND and CS. I think R2 is more likely just a limiter for input voltages that might otherwise damage the CS input.
measure what? those mosfet have 8205 written on them. and that resistor value are also same for both module.
My question is, where do the two numbers originate, where did you get them? 1A and 2A?
in there marketing materials. like where i brought them from.
So if it's mosfet what do think i should look for in the mosfet datasheet?
Whose marketing materials? Did it ever occur to you that they might be incorrect?