Reference Design Note

MagI3C Power Modules

DNS005 MagI3C Multi Color LED Driver

DNS005 V1.0

Alexander Zeller

– June 2019

Page 3/20

Copyright © Würth Elektronik eiSos GmbH & Co. KG

The LDHM (172946001) of the Würth Elektronik MagI³C Power Module Series is an LED driver based on a floating buck

regulator (see Figure 4). The module is able to deliver both constant and pulsed currents. The TO263 package integrates

the inductor, the free-wheeling diode and the regulator IC. It delivers an output current of up to 450mA at an output voltage

from 4,5V to 60V. The output voltage is limited by the input voltage of the module as the input voltage must be equal to or

greater than the desired output voltage for proper operation.

Figure 4: Floating Buck Topology

LED-

LED+

LED+

VIN

controller

CIN

COUT

Rsense

PGND

Floating buck

CIN

LED+

DIM

PGND

ISET

IFIX

LED-

Module

AGND

1

3

EP

6

VIN

2

LED+

7

5

4

RIADJ

High Power LED String

COUT

Figure 3: Typical LDHM Circuit Diagram