Datasheet

WPMDB1400362Q / 171040302
MagI
3
C Power Module
VDRM – Variable Step Down Regulator Module
we-online.com Würth Elektronik eiSos GmbH & Co. KG – Data Sheet Rev. 1.0
© May 2016 28/48
The curves below show a comparison among the input currents under three different soft-start conditions:
• Default soft-start (without any additional external capacitor)
• Soft-start with two different values of C
SS
.
The first peak (same for any condition) is due to the initial charge of the capacitors at the input (C
IN
). This current peak is not
affected by the soft-start. Therefore it can´t be reduced by different soft-start capacitor values.
The right part of the diagram shows the smooth rise of the input current during the start-up. The different slope of the rising
edge of the currents is defined by the different soft-start durations.
0
2
4
6
8
10
12
0 2 4 6 8 10
Input current [A]
Time [ms]
Input current at start up with different soft-start capacitors - V
IN
= 5V
without Css
Css = 2.2nF
Css = 4.7nF