The programmable current limit threshold and full-scale cable compensation voltage are determined by the values of the R_SNS, R_SET, R_ILIMIT, and R_IMON resistors. Refer to Figure 10-15.

• R_SNS is the current sense resistor. The recommended voltage across R_SNS under current limit should be approximately 50 mV as a compromise between accuracy and power dissipation. For example, if current limiting is desired for I_OUT(MAX) ≥ 3.3 A, then R_SNS = 0.05 V / 3.3 A = 0.01515 Ω. Choose a standard value of 15 mΩ.
• R_SET determines the input current to the transconductance amplifier and current mirror. The amplifier balances the voltage to be equal to that across R_SNS. Choose a R_SET value to produce an I_SET current bfrom 75 - 180 µA at the desired I_OUT(MAX). Considering 50 mV across R_SET, a value of 300 Ω will provide approximately 166 µA of I_SET current to the amplifier and mirror circuit. Care should be taken to limit the I_SET current below 200 µA to avoid saturating the internal amplifier circuit.
• R_ILIMIT in conjuction with the 0.5 × I_SET current produces a voltage on the ILIMIT pin which is proportional to the load current flowing in R_SNS. For details on setting the current limit, see Current Limit Setting using R_ILIMIT.
• R_IMON in conjuction with the 0.5 × I_SET current produces a voltage on the IMON pin which is proportional to the load current flowing in R_SNS. For details on setting the current limit. see Cable Compensation.

Figure 10-15 Current Limit and Cable Compensation Circuit