Hello,
I had firstly posted my query in the wrong forum and the rep there did assist but he suggests i still consult this forum. http://e2e.ti.com/support/power_management/battery_management/f/179/t/349370.aspx
My main query regards the effects on connecting the fuel gauge data lines which are ground referenced to AGND and GND on BAT- to a micro-controller whos ground reference will be PACK-.
I know the I2C wouldn't have any issues with the -0.125 to +0.125v ground difference but i don't know if perhaps the data lines would act as a current path between the two ground levels and affect the current reading.
One solution would be to change AGND and GND to PACK- so all reference the same ground, but i don't know if this would affect the fuel gauge's references. Its a 24V pack and so introducing a possible +/- 0.125V change to the voltage reading would affect it too much?
A 3rd solution would be to do an isolated buffer eg ISO1540.
Thanks,
Stuart