Supplying standby voltage to memory and wakeup circuitry to wake a computer from a low power mode

A method of power management for a computer comprising the steps of:

• a dual mode power supply supplying at least a normal voltage when the computer is in a normal operating mode;
• storing a state of the computer in a computer memory;
• placing a computer in a power saving mode, the power supply supplying a standby voltage to the computer memory and to specific devices that may be involved in waking the computer and ceasing to supply the normal voltage when the computer is placed in the power saving mode, the normal voltage provided at a normal current and the standby voltage provided at a standby current that is less than the normal current, the voltages of the normal power output and the standby power output being approximately the same voltage;
• one or more of said specific devices detecting computer activity while the computer is in the power saving mode;
• generating a wake signal in response to said step of detecting activity;
• controlling the power supply to supply the normal voltage to wake the computer in response to the wake signal;
• and
• restoring the state of the computer based on the information stored in the computer memory.

An apparatus for waking a computer from a power saving mode comprising:

• a dual mode power supply supplying a normal voltage during a normal operating mode and only a standby voltage during a power saving mode, the normal voltage provided at a normal current and the standby voltage provided at a standby current that is less than the normal current, the voltages of the normal power output and the standby power output being approximately the same voltage;
• a computer memory coupled to the power supply and receiving only the standby voltage storing a state of the computer while the computer is in a power saving mode;
• an input/output (I/O) device coupled to the power supply, the I/O device generating a wake signal in response to detecting computer activity while the computer is in a power saving mode;
• a power management device coupled to the I/O device and the power supply the power management device receiving the wake signal and controlling the power supply to restore the normal voltage in response to the wake signal.

A power management system for a computer comprising:

• a dual mode power supply supplying at least a normal operating voltage to the computer during a normal operating mode and supplying a standby voltage only to a portion of the computer during a power saving mode, the normal voltage provided at a normal current and the standby voltage provided at a standby current that is less than the normal current, the voltages of the normal power output and the standby power output being approximately the same voltage;
• a power management device coupled to the power supply;
• a wake device coupled to the dual mode power supply, the wake device detecting computer activity and generating a wake signal to the power management device;
• a computer memory coupled to the dual mode power supply and receiving only the standby voltage and storing a state of the computer during the power saving mode;
• and
• in response to the wake signal, the power management device controlling the dual mode power supply to supply the normal operating voltage, and restoring the state of the computer based on the state of the computer stored in the computer memory.

A method of waking a computer from a power saving mode comprising the steps of:

• generating a normal power output and a standby power output from a dual mode power supply, the normal power output provided at a normal current and the standby power output provided at a standby current that is less than the normal current, the voltages of the normal power output and the standby power output being approximately the same voltage;
• storing a state of the computer in a computer memory;
• during a power saving mode, supplying only the standby power output to the computer memory and to a portion of the computer that may be involved in waking the computer;
• detecting computer activity;
• generating a wake signal in response to detecting the computer activity;
• supplying the normal power output to the computer in response to the wake signal;
• and
• restoring the state of the computer based on the information stored in the computer memory.

An apparatus for waking a computer from a power saving mode comprising:

• a dual mode power supply supplying a normal power output during a normal operating mode and only a standby power output during a power saving mode, the normal power output provided at a normal current and the standby power output provided at a standby current that is less than the normal current, the voltages of the normal power output and the standby power output being approximately the same;
• a computer memory coupled to the power supply and receiving only the standby power output storing a state of the computer while the computer is in a power saving mode;
• an input/output (I/O) device coupled to the power supply, the I/O device generating a wake signal in response to detecting computer activity while the computer is in a power saving mode;
• a power management device coupled to the I/O device and the power supply, the power management device receiving the wake signal and controlling the power supply to restore the normal power output in response to the wake signal.