System for electronic control unit wake-up on movement of a controlled member and protection from motor back electromotive force
A system for waking an electronic control unit upon movement of a controlled member, such as a vehicle lift gate or window, and protecting the electronic control unit from motor back EMF are provided. The system includes a power drive unit coupled to the controlled member and to the electronic control unit for moving the controlled member. A comparator subsystem is coupled to the power drive unit and is configured to compare an electrical output of the power drive unit generated due to motor back electromotive force in response to a manual movement of the controlled member to an electrical reference to determine whether to wake the electronic control unit. The system detects manual movement of the controlled member, e.g. from unauthorized entry, and causes an alarm and/or for the motor to brake or to drive to counteract the manual movement of the controlled member.
1. A system for waking an electronic control unit upon movement of a controlled member, comprising:
a power drive unit including a motor coupled to the controlled member and in electrical communication with the electronic control unit for moving the controlled member and producing an electrical output by a back electromotive force in said motor in response to a manual movement of the controlled member;
wherein the electronic control unit is operable in an operational mode or in a sleep mode, and wherein the electronic control unit is configured to cause said motor to apply a braking force opposing the manual movement of the controlled member;
a comparator subsystem coupled to said power drive unit and configured to:
compare the electrical output to an electrical reference, and
wake the electronic control unit from the sleep mode into the operational mode based on the comparison of the electrical output of said power drive unit to the electrical reference.
2. The system for waking an electronic control unit upon movement of a controlled member of claim 1 , wherein said comparator subsystem is further configured to dissipate the back electromotive force based on the comparison of the electrical output of said power drive unit to the electrical reference.
3. The system for waking an electronic control unit upon movement of a controlled member of claim 1 , wherein the controlled member is a lift gate of a vehicle.
4. The system for waking an electronic control unit upon movement of a controlled member of claim 1 , wherein the controlled member is a sliding closure of a vehicle.
5. The system for waking an electronic control unit upon movement of a controlled member of claim 1 , wherein the controlled member is a window of a vehicle.
6. The system for waking an electronic control unit upon movement of a controlled member of claim 1 , wherein said comparator subsystem includes a differential amplifier to compare the electrical output to the electrical reference.
7. The system for waking an electronic control unit upon movement of a controlled member of claim 6 , wherein the electrical reference is a predetermined voltage.
8. The system for waking an electronic control unit upon movement of a controlled member of claim 1 , wherein the electronic control unit is configured to measure a speed of the controlled member.
9. The system for waking an electronic control unit upon movement of a controlled member of claim 1 , wherein the electronic control unit is configured to measure a speed of the controlled member; and
wherein the braking force is proportionate to the speed of the controlled member.
10. The system for waking an electronic control unit upon movement of a controlled member of claim 9 , wherein the electronic control unit is configured to vary the amount of the braking force using pulse width modulation.
11. The system for waking an electronic control unit upon movement of a controlled member of claim 1 , wherein the electronic control unit is configured to selectively short said power drive unit to ground to cause said motor to apply the braking force opposing the manual movement of the controlled member.
12. The system for waking an electronic control unit upon movement of a controlled member of claim 1 , wherein the electronic control unit is configured to selectively connect a resistive element to one or more motor terminals of said motor to cause said motor to apply the braking force opposing the manual movement of the controlled member.
13. The system for waking an electronic control unit upon movement of a controlled member of claim 12 , wherein the electronic control unit is configured to selectively connect the resistive element between two or more of the one or more motor terminals of said motor to cause said motor to apply the braking force opposing the manual movement of the controlled member.
14. The system for waking an electronic control unit upon movement of a controlled member of claim 1 , wherein the electronic control unit is configured to selectively connect an electrical power supply to said motor to apply the braking force opposing the manual movement of the controlled member.
15. The system for waking an electronic control unit upon movement of a controlled member of claim 1 , wherein said power drive unit includes a gearset configured to provide a speed reduction between an output shaft of said motor and a driven shaft coupled to move the controlled member.
16. The system for waking an electronic control unit upon movement of a controlled member of claim 1 , wherein one of said comparator subsystem or said electronic control unit is configured to generate an alarm signal in response to the manual movement of the controlled member.
17. A system for protecting an electronic control unit from back electromotive force comprising:
a power drive unit coupled to a controlled member and to said electronic control unit for moving the controlled member;
wherein the electronic control unit is operable in an operational mode or in a sleep mode; and
said electronic control unit adapted to:
wake up from the sleep mode into the operational mode using an electrical output of said power drive unit generated in response to a manual movement of the controlled member,
dissipate the electrical output of the power drive unit in response to the manual movement of the controlled member, and
cause a motor of the power drive unit to apply a braking force opposing the manual movement of the controlled member.
18. A method for operating an electronic control unit, comprising:
waking the electronic control unit from a sleep mode into an operational mode using an electrical output of a power drive unit in response to a manual movement of a controlled member coupled to the power drive unit;
detecting the manual movement of the controlled member; and
causing a motor of the electronic control unit to apply a braking force opposing the manual movement of the controlled member in response to detecting the manual movement of the controlled member.
19. The method of claim 18 , wherein causing the motor of the electronic control unit to apply the braking force further comprises causing the motor to apply a passive drag opposing the manual movement of the controlled member.
20. The method of claim 18 , wherein causing the motor of the electronic control unit to apply the braking force further comprises causing the motor to apply a driving torque opposing the manual movement of the controlled member.