SNVSBJ0B December 2019 – August 2021 LM5170
PRODUCTION DATA
To achieve the highest regulation accuracy over wider load range, target to create 50 mV of VCS at full current. Therefore, RCS must be selected as Equation 47:
Ideally, a 1.5-mΩ current sense resistor is chosen for this example. However, due to availability, a standard non-inductive 1-mΩ current sense resistor is selected, namely,
Because RCS conducts the same current as the power inductor, its power dissipation is also determined by ILm_RMS.
If the selected RCS has parasitic inductance (assuming it is 1 nH), it must be compensated, and the compensation capacitor CCS must satisfy Equation 37.
Select the closest standard capacitor, CCS = 0.47 µF.
For optimal performance, it is good practice to add a 100-pF ceramic capacitor at each current sense pin to filter out common-mode noise, as shown in Figure 9-9.