WPMDL110xxx1S / 17301xx78

MagI

FDSM – Fixed Step Down Regulator Module

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Würth Elektronik eiSos GmbH & Co. KG – Data Sheet Rev. 1.0

© November 2015

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BLOCK DIAGRAM

CIRCUIT DESCRIPTION

The MagI³C Power Module 173xxxx78 is based on a non-synchronous step-down regulator with integrated MOSFET, free-

wheeling diode, power inductor, input and output capacitors. The control scheme is based on a Current Mode (CM)

regulation loop.

compares this signal with the internal 0.8V reference. The error signal is amplified and controls the on-time of a fixed

frequency pulse width generator. This signal drives the power MOSFET.

The Current Mode architecture features a constant frequency during load steps. Only the on-time is modulated. It is

internally compensated and stable with low ESR output capacitors and requires no external compensation network.