Data Sheet

WLMDU9456001JT / 172946001
MagI
3
C Power Module
LDHM - LED Step Down High Current Module
We-online.com Würth Elektronik eiSos GmbH & Co. KG – Data Sheet Rev. 1.0
© May 2016 18/35
The 172946001 could work properly also without any C
OUT
. In this case the inductor ripple will be added to the LED current,
as shown in the picture below.
Considering the frequency range of the ripple oscillations (800kHz), it does not lead to any visible flickering of the emitted
light. Nevertheless the presence of a certain ripple in the LED current increases the LED junction temperature. This
accelerates the aging of the LED and reduces its lifetime. Higher LED temperature causes the efficiency of the LED to drop.
In addition, electromagnetic emissions are increased due to the presence of the current ripple along the complete LED string
and connection wires.
Therefore a small MLCC output capacitor of 2,2µF is anyway recommended.
0
100
200
300
400
500
0 2 4 6 8 10
LED Current [mA]
Time [µs]
LED current with and without output capacitor
Without Cout
With Cout