×

POWER FEED CONTROL CIRCUIT FOR ON-VEHICLE ELECTRONIC CONTROL APPARATUSES

  • US 20080238192A1
  • Filed: 12/27/2007
  • Published: 10/02/2008
  • Est. Priority Date: 03/28/2007
  • Status: Active Grant
First Claim
Patent Images

1. A power feed control circuit for a plurality of on-vehicle electronic control apparatuses to which powers are fed from an on-vehicle battery through an output contact of a power source relay that is operated in response to a power source switch, characterized in:

  • that the plurality of on-vehicle electronic control apparatuses consist of a first on-vehicle electronic control apparatus including a first microprocessor which controls a first group of electric loads in response to operation states of a first group of input sensors and contents of a first nonvolatile program memory, and a second on-vehicle electronic control apparatus including a second microprocessor which controls a second group of electric loads in response to operation states of a second group of input sensors and contents of a second nonvolatile program memory;

    that said first on-vehicle electronic control apparatus and said second on-vehicle electronic control apparatus include serial communication interface circuits which are connected with each other, respectively;

    that said first on-vehicle electronic control apparatus includes an energization control circuit which drives the power source relay;

    that said first nonvolatile program memory contains programs which serve as first input/output control means, and also programs which serve as first save processing means and save completion reception confirmation means;

    that said second nonvolatile program memory contains programs which serve as second input/output control means, and also programs which serve as second save processing means and save completion report transmission means;

    that, when said power source relay has its electromagnetic coil energized by said energization control circuit, its output contact is closed to close power feed circuits for said first on-vehicle electronic control apparatus and said second on-vehicle electronic control apparatus, thereby to start operations of said first microprocessor and said second microprocessor;

    that said energization control circuit is configured of a logical sum product between a drive start command signal, which energizes said electromagnetic coil upon closure of the power source switch, and a self-holding command signal, which responds to a generation output of said first microprocessor having started operating;

    that said first save processing means is means for acting in a delay operation period until the operation of said first microprocessor is stopped in accordance with opening of said power source switch, thereby to execute first information save processing in which save information such as learnt data or detected abnormality information, stored in a volatile RAM memory, is stored in a first nonvolatile data memory, or/and first origin return processing in which actuators being some of the electric loads that are driven by said first microprocessor are returned to their initial positions;

    that said second save processing means is means for acting in a delay operation period until the operation of said second microprocessor is stopped in accordance with the opening of said power source switch, thereby to execute second information save processing in which save information such as learnt data or detected abnormality information, stored in a volatile RAM memory, is stored in a second nonvolatile data memory, or/and second origin return processing in which actuators being some of the electric loads that are driven by said second microprocessor are returned to their initial positions;

    that said save completion report transmission means and said save completion reception confirmation means are means for acting when said second microprocessor has completed its save processing operation by said second save processing means, whereby said second microprocessor reports and transmits a save completion state through said serial communication interface circuits, while said first microprocessor confirms reception of the transmitted state; and

    that said energization control circuit stops a self-holding operation for said electromagnetic coil in a case where said first microprocessor has completed its save processing operation by said first save processing means and where it has confirmed the completion state of the second save processing operation by said save completion reception confirmation means, whereby operation states of said power source relay are generally managed by said first microprocessor.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×