BQ76940: the REGSRC MOS is damage

Big Bill

Expert 1980 points

Part Number: BQ76940

Dear All:

I use the BQ76940 to design the 16s bms, when I do the OCD testing, I find the the MOS Q38 between the Cell 15 and REGSRC is damage ,as below is schematic, and the DS wave, can you explain what cause

the result. Thanks~

over 5 years ago

0 Matt Sunna over 5 years ago

TI__Guru* 80083 points

Hi Bill,

I think a diode / resistor pair is needed to protect the FET by reducing the power during a heavy load. Section 9 of this app note discusses this need in much more detail: http://www.ti.com/lit/pdf/slua749

You can also refer to this 15s reference design to see example component values: http://www.ti.com/tool/TIDA-00255

Best regards,

Matt

Power management

Power management forum

BQ76940: the REGSRC MOS is damage