BQ2057 battery charger

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Hello,

 

i developed PCB whit BQ2057 li ion charger. For the schematics, i selected application circuit from page 10 in datasheet, for 0.5A charge current.

Now that i am testing i actually do get 0.5A charge current, but what do i have to do to increase it to 1A?

I see that equation for Rsns on same page but it is not clear:
RSNS =V(SNS)/I(REG)

I need to calculate resistance of R sns resistor, to acquire 1A of current
but what voltage do i need to generate on Vsns pin, to tell IC to rgulate 1 amp of current to battery?

 

Or should i just get from the application example for 0.5A, where it says to use 0.2 Ohm resistor. So a 0.1 Ohm or 0.4 Ohm resistor shoudl output either 0.25A or 1A? Assuming that it is a linear mathetical equtaion. 

This topic has a solution.

Last Edited: Thu. Aug 23, 2018 - 10:00 AM
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BQ2057 is a Texas Instruments (TI) product - nothing to do with Atmel or Microchip.

 

For support, go to http://www.ti.com/product/BQ2057/support - which includes links to TI's forum ...

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Klemko wrote:
Now that i am testing i actually do get 0.5A charge current, but what do i have to do to increase it to 1A?

 

Ok, what does the datasheet read?  Not going to look for the datasheet, so you will have to provide the link.

 

This family of devices also is mentioned here a few times so a search of the forum might provide you with an answer.

 

JIm

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Datasheet link:

 

http://www.ti.com/lit/ds/symlink...

 

Page 10 

 

 

Thanks :D 

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Page 6 - current regulation.

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You mean PRECHARGE CURRENT REGULATION?   So 3mV is suppose to be Icharge MIN and 22mV is suppose to be Icharge MAX(for this IC 2A)?

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You seem to be overlooking the obvious - CURRENT REGULATION is the first one in the table. Vsns. 

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Oh so 95.4mV to 115.5mV. Thanks this is it yea, it also supports my calculatios. I did read this couple of times, but thought this is the voltage threshold at which the IC changes from CC to CV charging xD

 

Thanks for pointing it out.