To keep maximum voltage on the SNS pin at an acceptable range for the system, calculate the R_SNS as in Equation 12. To achieve better current sense accuracy. A 1% accuracy or better resistor is preferred.

For this application, an RSNS value of approximately 1 kΩ can be chosen to satisfy the equation requirements.

In other applications, more emphasis can be put on the lower end measurable values, which can increase RSNS. Likewise if the higher currents are of more interest the R_SNS can be decreased. Note that the maximum current that can be measured without saturation is 6 A.

Having the maximum SNS voltage scale with the DIAG_EN voltage removes the need for a Zener diode on the SNS pin going to the ADC.

The current limit must be set to an acceptable level, so with the KCL tolerances, the current limit of 4A is chosen. To set the programmable current limit value at 4 A , calculate the R_LIM as in Equation 12.

For a more accurate current limit estimation with the error tolerances of KCL see the Current Limit Accuracy section and use the graph to estimate the error at each desired current limit value.

TI recommends R_PROT = 5 kΩ to ensure the current going into the digital pins (EN, DIAG_EN, LATCH) is limited.

TI recommends a 1-kΩ resistor and 200-V, 0.2-A diode (BAS21 for example) for the GND network.