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BQ2980: Shutdown function of CTR-Pin

Part Number: BQ2980

Hello,

i am currently using the BQ298010 as a protector for my LiIon charging board.

Everything is working as expected except from the CTR Pin function: I am able to trigger the Reset-Function by pulling the CTR Pin high to 3.3V. But I am not able to trigger the Shutdown-function, because the System resets itself after applying 3.3V on CTR pin for >5.4 seconds, as mentioned in the datasheet.

I am expecting to use the Shutdown-function to conserve Battery. I then want to wake the device up again by applying a charging Voltage like it's the case when the BQ2980 enters Shutdown-mode because of UVP.

I will attach the schematics of my charging circuit.

Kind regards

Björn Ellensohn

SMS-Battery Controller.pdf

  • Hi Björn,

    This should work as you describe - applying a high logic voltage on the CTR pin for 5.4 seconds should put the device into Shutdown mode and connecting a charge should bring the device back into normal mode. However, you schematic shows the PACK pin is connected to BATCON+ instead of PACK+? It also looks like PACK- and BATCON- connections are reversed. See Figure 9-6 in the datasheet for a typical schematic example.

    Best regards,

    Matt

  • Hello Matt,

    it looks like i misunterstood the supplied schematic. In my case, BATCON connects to the battery terminals. I suppose I connected the circuit the wrong way. Can you please confirm my mistake? Thank you for your help.

    Kind regards

    Björn

  • Hi Björn,

    Yes, I think that is the issue. Since the PACK pin is not connected to PACK+, it will not be able to detect when the charger has been connected. And since BATT- and PACK- are reversed, I think the current will measure in the opposite direction.

    Best regards,

    Matt