September 2013

Rev 2

1/22

AN2334

Application Note

Complete car door module

Introduction

A car door module typically consists of a rubber-sealed carrier, onto which a variety of door

components such as the window lift mechanism, the wing mirror electric motor, the wiring

harness, the loud speaker, the door latch inner release cable, locks and various switches

are fitted, forming a “cassette”.

The trend in both Europe and the U.S. is to increase the complexity of the door module by

adding more electronic features needed to drive all door loads and functions, with the

possibility to connect the module to other car subsystems via standard automotive

communication protocols (LIN, CAN).

Among many of these automotive subsystems, the connectivity via a single wire,

decentralizing electronic modules, reduces the number of wires required and in turn reduces

wiring harness weight, contributes significantly to overall vehicle weight reduction. This is of

concern to auto manufacturers, who are constantly striving to reduce vehicle weight and to

improve fuel efficiency.

In this document, an electronic module is presented that controls all the car door functions,

including the window lift, all latching/locking operations, wing mirror movement, mirror turn

indicator light, defroster and some lamps. To reduce the risk of bodily injury, especially to

children, this module also includes an advanced trapping detection feature for the window lift

motor, which stops the window if a body member such as a finger, a hand or an arm is

introduced into the window climbing area during the window climbing process. A low-cost,

high performance, antipinch algorithm based on monitoring the window motor driver current,

has been developed.

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