Automotive computer system and method whereby responsive to detecting engine cranking main processor enters a suspend mode and current state of devices are stored in volatile memory

• US 6,601,176 B1
• Filed: 09/08/1999
• Issued: 07/29/2003
• Est. Priority Date: 09/08/1999
• Status: Expired due to Term

• Current Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Original Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Inventors: Wright, David P., Alexander, Douglas, Messina, Vincent, Konstantine, John Frank
• Primary Examiner(s): Lee, Thomas
• Assistant Examiner(s): Trujillo, James K.
• Application Number:
  US09/392,146
• Time in Patent Office: 1,420 Days
• Field of Search: 713/1, 713/300, 713/330, 713/340, 713/320, 713/323, 713/324
• US Class Current: 713/300
• CPC Class Codes: G06F 1/24 Resetting means
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C

Abstract

A multimedia/personal computer based system for operating information, communication, and entertainment devices in a mobile vehicle uses a power management system which provides power to volatile ram during engine startup. During engine startup, battery voltage decreases to a point that most electronic devices can not function and may be harmed. A low power microprocessor off-board of a main processor board, which is a complex instruction set (CISC) processor system, switches a primary voltage regulator, which provides a plurality of regulated voltages to the main processor board, off to reduce power requirements. The main processor board stores a state of predetermined peripheral devices in volatile ram and then turns the devices off. The main processor then goes into a suspend mode awaiting a wake up signal from the low power microprocessor. A secondary voltage regulator turns on to supply power to the volatile ram when the primary voltage regulator is turned off.

Claims

1. A power management system for providing energy to volatile ram in a processor based electronic system installed in a vehicle having an engine, said vehicle including an engine crank signal for detecting a startup condition of said engine and having a main electrical power source, said power management system comprising:

a main processor board for performing information processing including an input for said engine crank signal and a main processor coupled to said volatile ram;

a vehicle input/output processor board for performing real time processing of vehicle interfaces, user inputs, and overall power management of a plurality of peripheral devices, said input/output processor board being coupled to said main processor board and including an input for said engine crank signal;

a primary voltage regulator for powering said main processor board and generating a primary regulated output votage in response to a primary input voltage, said primary voltage regulator being coupled to said input/output processor board and being coupled to said main electrical power source; and

a secondary voltage regulator coupled to said volatile ram and responsive to said engine crank signal to provide power substantially only during startup of said engine, said secondary voltage regulator generating a secondary regulated output voltage in response to a secondary input voltage and being coupled to said main electrical power source;

wherein said primary voltage regulator provides said primary regulated output voltage when said primary input voltage is within a primary voltage range;

wherein said secondary voltage regulator provides said secondary regulated output voltage when said secondary input voltage is within a secondary voltage range and wherein said secondary voltage range includes voltages lower than said primary voltage range; and

wherein said main processor board detects said engine crank signal and enters into a suspend mode in which predetermined devices controlled by said main processor board are shut down and in which said main processor board stores a current state of said predetermined devices into said volatile ram.

2. The system according to claim 1 wherein said vehicle input/output processor board monitors said engine crank signal and wherein said vehicle input/output board sends a wake up signal to said main processor board after said vehicle input/output processor board detects said engine crank signal has transitioned to an off state.

3. The system according to claim 1 wherein said engine crank signal is transmitted from an engine control processor.

4. The system according to claim 1 wherein said secondary voltage regulator is directly connected to said volatile ram and is located on said vehicle input/output processor board.

5. The system according to claim 1 wherein said secondary voltage regulator is in parallel with said primary voltage regulator and wherein said primary voltage range is greater than about 9 v and said secondary voltage range is greater than about 4 v.

6. The system according to claim 1 wherein said main processor board completes entry into said suspend mode within about 14 ms of receiving said engine crank signal.

7. The system according to claim 1 wherein said secondary voltage regulator powers said volatile ram on said main processor board only after said primary voltage regulator shuts down due to reduced power availability during said engine startup condition.

8. A method of providing energy to volatile ram in a processor based electronic system installed in a vehicle with an engine and a main electrical power source, said vehicle including a vehicle ignition system which generates an engine crank signal when said engine is starting, said electronic system including a main processor board, a vehicle input/output processor board which generates a wake up signal when said engine crank signal transitions to an off state, a secondary voltage regulator and a primary voltage regulator both being coupled to said ram, said method comprising the steps of:

generating said engine crank signal in response to an operator requesting engine cranking;

entering a suspend mode in said main processor board in response to said engine cranking signal;

cranking said engine thereby reducing available power from said main electrical power source and causing said primary voltage regulator to shut down; and

powering said secondary voltage regulator during engine cranking wherein said secondary voltage regulator powers said volatile ram, said secondary voltage regulator adapted to sustain said volatile ram when said available power is insufficient to maintain operation of said primary voltage regulator.

9. The method according to claim 8 wherein said vehicle input/output processor board transmits said wake up signal to said main processor board after detecting said crank signal transition to said off state where upon said main processor board resumes a normal operating state.

10. A power management system for providing energy to volatile ram in a processor based electronic system installed in a vehicle having an engine, said vehicle including an engine crank signal for detecting a startup condition of said engine and having a main electrical power source, said power management system comprising:

a main processor board for performing information processing including an input for said engine crank signal and a main processor coupled to said volatile ram;

a vehicle input/output processor board for performing real time processing of vehicle interfaces, user inputs, and overall power management of a plurality of peripheral devices, said input/output processor board being coupled to said main processor board and including an input for said engine crank signal;

a primary voltage regulator for powering said main processor board and generating a primary regulated output voltage in response to a primary input voltage, said primary voltage regulator being coupled to said input/output processor board and being coupled to said main electrical power source; and

a secondary voltage regulator coupled to said volatile ram and responsive to said engine crank signal to provide power substantially only during startup of said engine, said secondary voltage regulator generating a secondary regulated output voltage in response to a secondary input voltage and being coupled to said mnain electrical power source;

wherein said primary voltage regulator provides said primary regulated output voltage when said primary input voltage is within a primary voltage range; and

wherein said secondary voltage regulator provides said secondary regulated output voltage when said secondary input voltage is within a secondary voltage range and wherein said secondary voltage range includes voltages lower than said primary voltage range.

11. A power management system for providing energy to volatile ram in a processor based electronic system installed in a vehicle having an engine, said vehicle including an engine crank signal for detecting a startup condition of said engine and having a main electrical power source, said power management system comprising:

a main processor board for performing information processing including an input for said engine crank signal and a main processor coupled to said volatile ram; and

a vehicle input/output processor board for performing real time processing of vehicle interfaces, user inputs, and overall power management of a plurality of peripheral devices, said input/output processor board being coupled to said main processor board and including an input for said engine crank signal;

wherein said main processor board detects said engine crank signal and enters into a suspend mode in which predetermined devices controlled by said main processor board are shut down and in which said main processor board stores a current state of said predetermined devices into said volatile ram.

12. A method of providing energy to volatile ram in a processor based electronic system installed in a vehicle with an engine and a main electrical power source, said vehicle including a vehicle ignition system which generates an engine crank signal when said engine is starting, said electronic system including a main processor board, a vehicle input/output processor board which generates a wake up signal when said engine crank signal transitions to an off state, a secondary voltage regulator and a primary voltage regulator both being coupled to said ram, said method comprising the steps of:

generating said engine crank signal in response to an operator requesting engine cranking;

cranking said engine thereby reducing available power from said main electrical power source and causing said primary voltage regulator to shut down; and

powering said secondary voltage regulator during engine cranking wherein said secondary voltage regulator powers said volatile ram, said secondary voltage regulator adapted to sustain said volatile ram when said available power is insufficient to maintain operation of said primary voltage regulator.

13. A method of operating a processor based electronic system installed in a vehicle with an engine and a main electrical power source, said vehicle including a vehicle ignition system which generates an engine crank signal when said engine is starting, said electronic system including a main processor board having a main processor, and said electronic system including a vehicle input/output processor board which generates a wake up signal when said engine crank signal transitions to an off state, said method comprising the steps of:

generating said engine crank signal in response to an operator requesting engine cranking;

entering a suspend mode of said main processor in response to said engine cranking signal wherein predetemitined devices controlled by said main processor board are shut down and wherein a current state of said predetermined devices are stored into a volatile memory.

14. A power management system for providing energy to volatile ram in a processor based electronic system installed in a vehicle having in engine, said vehicle including an engine crank signal for detecting a startup condition of said engine and having a main electrical power source, said power management system comprisings.

a main processor board for performing information processing including an input for said engine crank signal and a main processor coupled to said volatile ram;

a vehicle input/output processor board for performing real time processing of vehicle interfaces, user inputs, and overall power management of a plurality of peripheral devices, said input/output processor board being coupled to said main processor board and including an input for said engine crank signal;

a primary voltage regulator for powering said main processor board and generating a primary regulated output voltage in response to a primary input voltage, said primary voltage regulator being coupled to said input/output processor board and being coupled to said main electrical power source; and

a secondary voltage regulator coupled to said volatile ram to provide power substantially only during startup of said engine, said secondary voltage regulator generating a secondary regulated output voltage in response to a secondary input voltage and being coupled to said main electrical power source;

wherein said primary voltage regulator provides said primary regulated output voltage when said primary input voltage is within a first voltage range, said primary input voltage falling below said first voltage range during said engine crank signal;

wherein said secondary voltage regulator is activated and provides power to said volatile ram after receiving said engine crank signal; and

wherein said main processor board detects said engine crank signal and goes into a suspend mode in which predetermined devices controlled by said main processor board are shut down and in which said main processor board stores a current state of said predetermined devices into said volatile memory ram.