DRV8323: CSA Absolute Maximum Ratings

Hi Andriy,

For high current applications where the low side source current can reach hundreds of amps, the best practices would be to use low gain settings and low resistance shunt resistors in the hundreds of uOhms range. Specifically:

Shunt resistors: 

- Consider shunt resistors with high power continuous ratings, i.e. 8-10W. For instance, if a 500uOhm shunt is used, and the application uses maximum 100-A continuous current, then you'll need at least a 100^2*500u = 5W rated resistor. An example of such a resistor can be found here: https://www.koaspeer.com/pdfs/PSL2.pdf

- These resistors may be hard to find as they have been out of stock for majority of last year and this year so far. If you need that low of an equivalent resistance, you may place multiple shunts in parallel, i.e. five 2.5mOhm resistors. 

Gain settings:

- The main trade-off for CSAs is the lower the gain used, the higher the current range and lower the precision; the higher the gain used, the lower the current range and higher the precision. For high-current applications, it is recommended to use the smallest gain setting, i.e. 5 V/V.

- For instance, if the 500uOhm shunt is used and the application uses 100-A max continuous current, then this will generate a 0.05V voltage across the shunt. A gain setting of 5 V/V will see a difference of +/- 0.25V from VREF/2. 

Hope this helps!

Thanks,
Aaron