BQ2973: The Dout is always low

HongRen Chang

Part Number: BQ2973

Dear sir

I use the BQ2973 for the battery protection. Here is the schematic.

I used a DC power supply to add a 4V between BAT+ and BAT-. I found the CSD87313 is not on. I measued the Cout and Dout of BQ2973, Cout = 1 and Dout =0?

Why this is happened?

Thanks

Ren

over 6 years ago

0 WM5295 over 6 years ago

TI__Guru 54715 points

Hi Ren,
When the cell is first attached or the power supply is turned on, the part is receiving power from an under voltage condition. It needs a charger voltage or simulation of that to wake up. See the note in the box in section 9.4.1 of the data sheet, top of page 18. Apply a charger or momentarily short across the FETs to wake up the part.

0 HongRen Chang over 6 years ago in reply to WM5295

Intellectual 390 points

Dear Sir

Thanks for you answer.

It works as you said.

Thanks a lot

Ren

Power management

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BQ2973: The Dout is always low