ZHCSFE3B March 2016 – November 2017 LM5161
PRODUCTION DATA.
The soft-start feature of the LM5161 allows the converter to gradually reach a steady-state operating point, thereby reducing start-up stresses and current surges. When the EN/UVLO pin is above the EN/UVLO standby threshold VUVLO(TH) = 1.24 V (typ) and VCC exceeds the VCC undervoltage VCC(UV) = 3.98 V (typ) threshold, an internal 10-µA current source charges the external capacitor at the SS pin (CSS) from 0 V to 2 V. The voltage at the SS pin is connected to the noninverting input of the internal FB comparator. The soft-start interval ends when the SS capacitor is charged to the 2 V reference level. The ramping voltage at the SS pin produces a controlled, monotonic output voltage start-up. A minimum 1-nF soft-start capacitor must be used in all applications.