Design Win

A highly reliable trunk control solution based on FlightSense technology

Solution Description

This solution is a demonstrator of the capability to design a trunk lift using motor drivers with current sensing for safety, a microcontroller and non-automotive qualified FlightSense™ sensors to have a foot movement reliable detection for trunk opening.

Today's car manufacturers are required to come up with innovative new features to distinguish themselves in a very competitive market. One way to do this is to implement a hands-free solution to open or close a car's trunk to improve people's experiences with their vehicles.

With many car owners frustrated by the unpredictable behavior of their lift gates in many recent car models offering a similar application, our smart solution describes a simplified way for people to open or close their trunk using a predefined foot movement. It also includes a safety feature based on current sensing that prevents damage if there are obstacles when opening or closing the trunk.

ST's hands-free power liftgate solution only uses three components for a reduced bill of materials and a simpler design phase. Non-automotive FlightSense™ sensors located below the bumper are used to detect the foot movement under the trunk. Once the foot movement is detected, a general-purpose SPC58 C Line automotive microcontroller (SPC58EC80E5) will confirm the correct pattern and send a command to open or close the trunk to the two automotive-grade fully integrated H-bridge motor drivers (VNH7040AY) that synchronously drive the liftgate's two linear actuator motors. Of course, to ensure security, the hands-free solution only works if the vehicle is already unlocked and parked.

Note: Optionally, it is also possible to use a VNHD7008AY H-bridge motor driver which integrates a fully protected dual high-side driver as well as the drivers and protections for the two external power MOSFETs in a low-side configuration.

FlightSense is a registered and/or unregistered trademark of STMicroelectronics International NV or its affiliates in the EU and/or elsewhere.



  • Key Product Benefits

    FlightSense™ Technology

    A ranging sensor able to create from 1 to 64-zone mini depth map and multi-target detection up to 4 m, ST's 4th generation of FlightSense sensors are an all-in-one (emitter, receiver, and processor) system for an easy, cost effective, and small footprint integration.

    • ST’s latest FlightSense™ technology 
      • - True distance measurement, independent of target size, color, and reflectance
      • - Accurate and high-speed distance measurement
      • - All-in-one integrated module for easy integration
      • - Low power consumption
      • - Truly invisible 940nm illumination
    VNH7040AY fully integrated H-bridge motor driver

    A dual monolithic high-side driver with two low-side switches designed using ST's proprietary VIPower® M0-7 Technology, it features: 

    • - AEC-Q100 qualified 
    • - Multisense diagnostics and monitoring functions (obstacle detection) 
    • - Dedicated input signals to select motor direction and brake condition 
    • - PWM operation up to 20 kHz to control the motor's speed in all possible conditions
    SPC58 C Line automotive microcontroller

    A cost-efficient, multi-core microcontroller designed for secure onboard communication systems in connected vehicles, it features: 

    • - Versatile low-power modes 
    • - Rich set of peripherals 
    • - Enhanced modular I/O subsystem 
    • - ASIL-B safety standard support 
    • - Comprehensive AutoDevKit development ecosystem
  • All Features

    • Technical
      • Supply voltage: 12V
      • Sensor supply voltage: 3.3V
      • Digital logic supply voltage: 5V
      • Synchronous driving of Trunk motors
      • FOTA capability for application software
    • Perfromance
      • Maximum current for each motor : 35A
      • Foot movement pattern response time : 1s
    • Compatibility
      • All Key products are Automotive Grade
      • Application code is MISRA C 2012 compliant