Abstract

Automotive door handle systems continue to enhance user experience, safety, and reliability by incorporating new features and improving upon old ones. These features are enabled by different sensing technologies including magnetic sensors (anisotropic magneto resistive (AMR) and Hall-effect), capacitive sensors, and inductive sensors.

This document demonstrates the implementation of a deployable automotive door handle using magnetic and capacitive sensors to capture position data in a door handle demo design. Sensor design and testing methods are described, leveraging the hardware and software based demo, along with potential error sources and alternative sensing options, such as inductive sensing. The technologies covered in this app note include a Hall-effect sensor for detecting the open or close status of the door and an AMR angle sensor for the position of the handle. The application note illustrates the use and design of capacitive sensing for a touch button and the presence of a user's hand on the handle. This application note, but not the demo, also includes the use, design and implementation of an inductive sensor push button (as opposed to a capacitive touch button), as that is also a frequent option in today's vehicles.