ELECTRONIC APPARATUS AND AUTO WAKE-UP CIRCUIT THEREOF

• US 20090240965A1
• Filed: 03/12/2009
• Published: 09/24/2009
• Est. Priority Date: 03/21/2008
• Status: Active Grant

• Current Assignee: Xueshan Technologies Inc. (Wi-LAN Inc.)
• Original Assignee: MStar Semiconductor Incorporated (MediaTek, Inc.)
• Inventors: CHEN, CHIEN-SHENG, HSIEH, CHIH-YUAN
• Granted Patent: US 8,117,479 B2
• Time in Patent Office: Days
• US Class Current: 713/323
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3287 by switching off individual functional units in the computer system
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

The present invention relates to an electronic apparatus and an auto wake-up circuit thereof. The electronic apparatus comprises a main module for performing a main function of the electronic apparatus and generating a first control signal when the electronic apparatus enters a sleep mode; an auxiliary module, coupled to the main module, for performing an auxiliary function of the electronic apparatus and generating a second control signal; and a wake-up circuit module, coupled to the main module and the auxiliary module, for generating a third control signal based on the first control signal and the second control signal. The auxiliary module maintains the auxiliary function based on the third control signal while the electronic apparatus is in the sleep mode.

Claims

1. An electronic apparatus, comprising:

a main module, for performing a main function of the electronic apparatus, and generating a first control signal when the electronic apparatus enters a sleep mode;

an auxiliary module, coupled to the main module, for providing an auxiliary function to the electronic apparatus, and generating a second control signal; and

a wake-up circuit module, coupled to the main module and the auxiliary module, for generating a third control signal in accordance with the first control signal and the second control signal;

wherein, the auxiliary module maintains the auxiliary function in accordance with the third control signal in the sleep mode.

2. The electronic apparatus of claim 1, wherein the electronic apparatus is a hand-held electronic device.

3. The electronic apparatus of claim 1, wherein the auxiliary module is an RFID module or a GPS module.

4. The electronic apparatus of claim 1, wherein the second control signal is a pulse signal.

5. The electronic apparatus of claim 4, wherein the period of the pulse signal equals to or approximates the period according to which the auxiliary module maintains the auxiliary function.

6. The electronic apparatus of claim 1, wherein the control signal is generated when the electronic apparatus enters the sleep mode.

7. The electronic apparatus of claim 1, wherein the wake-up circuit module comprises:

a power storage device;

a charging unit, coupled to the power storage device, for charging the power storage device;

a discharging unit, coupled to the power storage device, for providing a discharge path to the power storage device in accordance with the second control signal; and

a comparing unit, coupled to the power storage device, for comparing a voltage of the power storage device with a predetermined voltage to generate the third control signal.

8. The electronic apparatus of claim 7, wherein the comparing unit is further coupled to the main module, and the predetermined voltage is generated in accordance with the first control signal.

9. The electronic apparatus of claim 7, wherein the discharging unit is further coupled to the main module, and the discharging path is associated with a level of the first control signal.

10. The electronic apparatus of claim 7, wherein the discharging unit comprises a switch device, and an on-and-off state of the switch device is controlled by the second control signal.

11. An auto wake-up circuit, applied to an electronic apparatus and used to maintain an operation of an auxiliary module of the electronic apparatus while the electronic apparatus is in a sleep mode, the auto wake-up circuit comprising:

a power storage device;

a charging unit, coupled to the power storage device, for charging the power storage device;

a discharging unit, coupled to the power storage device, for providing a discharge path for the power storage device in accordance with a first control signal; and

a comparing unit, coupled to the power storage device, for generating a second control signal by comparing a voltage of the power storage device with a predetermined voltage, in order to control the operation of the auxiliary module.

12. The auto wake-up circuit of claim 11, wherein the first control signal is generated by the auxiliary module when the electronic apparatus enters the sleep mode.

13. The auto wake-up circuit of claim 11, wherein a third control signal is generated by the electronic apparatus in the sleep mode and the predetermined voltage is generated according to the third control signal.

14. The auto wake-up circuit of claim 11, wherein a third control signal is generated by the electronic apparatus in the sleep mode and the discharging path is associated with a level of the third control signal.

15. The auto wake-up circuit of claim 11, wherein the first control signal is a pulse signal.

16. The auto wake-up circuit of claim 15, wherein the period of the pulse signal equals to or approximates the period according to which the auxiliary module operates in the sleep mode.

17. The auto wake-up circuit of claim 11, wherein the power storage device is a capacitor.

18. The auto wake-up circuit of claim 11, wherein the discharging unit comprises a switch device, and an on-and-off state of the switch device is controlled by the first control signal.

19. The auto wake-up circuit of claim 18, wherein the switch device is a transistor.

20. The auto wake-up circuit of claim 11, wherein the comparing unit comprises an operational amplifier, which has a first input terminal coupled to the predetermined voltage, a second input terminal coupled to the power storage device, and an output terminal outputting the second control signal.