+ Post New Thread
Results 1 to 6 of 6
  1. #1
    Member level 1
    Points: 611, Level: 5

    Join Date
    Oct 2014
    Posts
    37
    Helped
    0 / 0
    Points
    611
    Level
    5

    What is the effect of 100 microseconds(us) transient in a automobile battery?

    A typical embedded system, let's say Transmission or Power Train Electronic Control Unit (ECU) is powered by automobile Battery.

    Battery voltage is at 12 Volts. If the battery voltage drops to 0 Volts in 5 us and stays at 0 V for 100 us, then rises back to 12V in 5 us, what impact will this have on Microcontroller memories, different microcontrollers inputs like Analog, Digital, PWM, etc. And different outputs like Digital, PWM etc.

    Will the contents of I/O and memories like SRAM, Program Flash, Data Flash change due to this transient?

    The microcontroller on the ECU is Infineon Aurix TX29x.

    - - - Updated - - -

    Correction! The Microcontroller is Infineon Aurix Tricore TC29x

    •   Alt10th January 2017, 22:36

      advertising

        
       

  2. #2
    Super Moderator
    Points: 40,121, Level: 48
    Awards:
    Most Frequent Poster

    Join Date
    Apr 2014
    Posts
    8,207
    Helped
    1982 / 1982
    Points
    40,121
    Level
    48

    Re: What is the effect of 100 microseconds(us) transient in a automobile battery?

    Hi,

    A rather hypothetical question. But I can't see any use behind such a question.

    How do you decide to bring a healthy car battery down to 0V and then back to 12V within microseconds?

    A microcontroller doesn't run on 12V. It runs on 5V, 3.3V or even less. So it needs some power supply, maybe a SMPS.

    Every microcontroller datasheet specifies the operation voltage range, for memories there is a "data retention voltage".
    But as said before this has nothing to do with battery voltage.

    ******
    You compare the wrong voltages.
    An example with temperature instead of voltage:
    If you want to boil an egg.....then the temperature of the water is what matters, not the temperature of the gas flame.

    Klaus



    •   Alt11th January 2017, 00:16

      advertising

        
       

  3. #3
    FvM
    FvM is offline
    Super Moderator
    Points: 225,268, Level: 100
    Awards:
    1st Helpful Member

    Join Date
    Jan 2008
    Location
    Bochum, Germany
    Posts
    38,764
    Helped
    11851 / 11851
    Points
    225,268
    Level
    100

    Re: What is the effect of 100 microseconds(us) transient in a automobile battery?

    Automotive EMC standards like ISO 7637 specify considerably stronger disturbances than you presume. If you want your design to work in the real automotive world, provide filters that are capable to deal with the ISO 6737 test pulses.



    •   Alt11th January 2017, 07:58

      advertising

        
       

  4. #4
    Advanced Member level 3
    Points: 4,417, Level: 15

    Join Date
    Jun 2016
    Posts
    930
    Helped
    105 / 105
    Points
    4,417
    Level
    15

    Re: What is the effect of 100 microseconds(us) transient in a automobile battery?

    I think he is talking about short circuit for a period of 100 us like some Mosfets used in electric vehicles shorting for 100 us.



  5. #5
    Member level 1
    Points: 611, Level: 5

    Join Date
    Oct 2014
    Posts
    37
    Helped
    0 / 0
    Points
    611
    Level
    5

    Re: What is the effect of 100 microseconds(us) transient in a automobile battery?

    >> How do you decide to bring a healthy car battery down to 0V and then back to 12V within microseconds?
    This is proprietary information.

    I'll check the memories data retention voltage.



    •   Alt11th January 2017, 15:40

      advertising

        
       

  6. #6
    Advanced Member level 5
    Points: 11,158, Level: 25

    Join Date
    Apr 2010
    Posts
    1,716
    Helped
    369 / 369
    Points
    11,158
    Level
    25

    Re: What is the effect of 100 microseconds(us) transient in a automobile battery?

    Even if the system is going to to 0v and then back to 12v within microseconds (with a propreitory way) ,
    the regulator supply filter can be sized for taking this sudden shock for few microseconds.



+ Post New Thread
Please login
--[[ ]]--