BQ77915:Charge with BQ77915

merve damar

Part Number: BQ77915

Hi all. I want to use BQ77975. ı will use 5s batteries. ı want to protect voltage, current, and temperature. ı have 24V power supply. I will make circiut in datasheet. ı want to connect with my power supply. can ı charge this 5 batteries. or need ı another IC for charge?

over 4 years ago

0 David Hien over 4 years ago

TI__Genius 10830 points

hi Merve,
BQ77915 is not a charger IC but a protection IC. I suggest you have a look here for an overview of our charger ICs.

0 merve damar over 4 years ago in reply to David Hien

Prodigy 70 points

thanks dear, so ı should use protection IC and Charge IC in my design. Am ı right? ı should use both.

0 David Hien over 4 years ago in reply to merve damar

TI__Genius 10830 points

Yes

0 merve damar over 4 years ago in reply to David Hien

Prodigy 70 points

What does it mean up to 50mA protection current? According to what should I choose the Rin resistance?

0 Matt Sunna over 4 years ago in reply to merve damar

TI__Guru* 81034 points

Hi Merve,

50 mA is the maximum cell balancing current. The cell balancing internal FET resistance is typically around 12 mohm - the datasheet suggests using an Rin of 33 ohms if you want the maximum balance current without external balancing FETs (4V / (33+12+33) ~= 50 mA).

This video give a good overview of the cell balancing feature of the BQ77915: https://training.ti.com/how-cell-balancing-feature-works-bq77915

Best regards,

Matt

Power management

Power management forum

BQ77915:Charge with BQ77915