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Brett's Arduino 8x Smart Charger / Discharger
(03-27-2018, 11:11 PM)brettwatty Wrote: Yeah the bloody TP4056's I have are not even close to +- 0.07245V. 
Thinking of adding a fan on the side.  
I am using IRF540N N-Channel FETS rated at 28A max never get hot for me I only used them because a have a bag of 100 left over from another project. 
I have SI2306DS SOT23 for the polarity protection rated for 2.8A @ 4.5V VGS I will eventually use IRLML2502TRPbF-1 SOT23. 
My board is designed for either THT or SMD components for all the resistors and FETS.
Polarity protection is a must for me so many TP4056 fried because of dumb mistakes and last thing you want is a -4.20V on an Analog input  Big Grin .

Cool thx ..will look int to adding the protections i think .. even tho i have only ±700 cells left to test Smile for now 

Have you tried to cut power with still cells in slots ?
mine was powering everything from those cells(used only 1 for test .. not to fry up the MEGA and multiplexers)... yes i use multiplexers for inputs of analog..
Constantine had the same issue in his build, and he removed multiplexers i think.
I use dividers to limit inputs, because i need 20 cell tester not 8 Wink Smile

maybe we all could add the backups from 18650 and boost/buck converters for emergency situations Big Grin as we all have enough of 18650 Big Grin
Yeah EGOksy I have the same issue. From some reading I found that the power is flowing from the analog pins, through the internal clamping diodes, to the Vcc line. So will either need to find a way to disconnect the analog pins when there is no power from the 5V regulator (transistor maybe) or I can put some 10K resistors in between the battery + to the analog pins. Apparently this is bad as those diodes are not rated for much current. Yeah the backup power is a good idea. I the future I am also thinking of making a Master module and Slave modules with multiplexer and shift registers. But for the moment I want refine my code.
Looking pretty legit there.   Cool
New video. Check it out. Cheers

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Proceed with caution. Knowledge is Power! Literally! Cool 
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Hello. Great work. When will you release the pcb files?
Neat. I wants one!
15s120p  Confused
Great project! I suggest rest the battery for one minute too.
Testing cells
Edit: Bloody new EasyEDA update broke the PCB design. Fu*k

So hold off on printing it until I fix the board. Cheers

I would hold of this one as there is no ESP8266 WIFI yet.

Let me know what you think.
Re the FETs getting hot for EGOksy posted earlier, check the gate "on" voltage for the FETs you're using is high enough & not in the threshold region wheer the FET is only partly on. FETs like these should be pretty much stone cold with several amps going through them when properly "on". You might have to pick a different FET with "logic level" gate threshold.
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