BQ34Z100: Golden file example, SOC accuracy and current sense input resistors questions

Part Number: BQ34Z100

My customer has the following questions:

1.      Can you provide us with an example golden file for the BQ34Z? The cell that we will be using is INR18650_F1L (Li-ion) and GP210AAHCB (NiMh), both cell data sheets are attached. Can you please check and confirm if you already have the Chem ID and the golden file for these cells?. If not, what is the process of getting the files?

2.      Does the Gauge require to do a calibration over time to main the SOC accuracy?, does it need host intervention?

3.      In the flags() status register, what action is expected from the host if the condition flag (CF) is set?

 

 

4.      The Rsense that we are currently using is 20mohm, is it OK or do we need to change it for better accuracy?

5.  We have to also consider any intrinsic safety (IS) implications for the design and as such I have the below question.

On pg. 47 of the datasheet, the schematic shows 2 low pass filters , one for each node across the sense resistor. The values are R5, R6=100ohm, C5, C6 = 0.1uF. The cut off frequency is around 16KHz.

 

We will need to increase the resistance from 100ohm to 470ohm for IS requirements and as such to maintain the cut off frequency, have to change the capacitors to 22nF. So the new values will be R5, R6 = 570ohm, C5, C6= 22nF.

 

Do you see any concern with this change, I believe both these nodes should be high impedance and changing resistance from 100ohm to 470ohm should have minimal impact?. Can you please confirm and also pose this question to the factory if this change is OK.

Thanks!

Best Regards, Mark P