AN2334 Datasheet, PDF (1/22 Pages) STMicroelectronics – Complete car door module

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.
September 2013
Rev 2
1/22
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