BQ24040: 0V lithium battery - resetting the protectory circuit of battery

Muhammed Alan

Part Number: BQ24040

Hello

After the battery voltage drops under 2.6V, the protection circuit of battery is disables the power. At this case BQ24040 is not charging the battery. is there any possible solution for this?

Best Regards,

over 4 years ago

0 Anthony P Pham over 4 years ago

TI__Mastermind 23410 points

Hi Muhammed,

Would you be able to share what charge current you are setting with the BQ24040 or circuit schematic? The issue may be that the current is too small for the protection circuit to allow for the connection to charge the battery.

0 Muhammed Alan over 4 years ago in reply to Anthony P Pham

Prodigy 30 points

Hi Anthony,

Iset = 1.8kR - 300mAh and preterm = 1kR. Battery is standart one cell Li-Po battery.

Best Regards,

0 Anthony P Pham over 4 years ago in reply to Muhammed Alan

TI__Mastermind 23410 points

Hi Muhammed,

It looks like with the preterm at 1-kOhm, the pre-charge that would be being applied is 10% of the fast charge. Based on the 1.8-kOhm at ISET, the fast charge is 300mA which you've mentioned so the pre-charge is 30mA.

This pre-charge value may be too low for the protection circuit, can you try increasing the resistor at the PRETERM pin?

0 Muhammed Alan over 4 years ago in reply to Anthony P Pham

Prodigy 30 points

Hi Anthony,

Thank you for quick reply. Yes that was the case. When ı increased the PRETERM resistor problem is solved.

Best Regards,

Power management

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BQ24040: 0V lithium battery - resetting the protectory circuit of battery