Portable electronic device and method

• US 6,242,892 B1
• Filed: 04/30/1999
• Issued: 06/05/2001
• Est. Priority Date: 09/03/1997
• Status: Expired due to Term

• Current Assignee: North Star Innovations Inc. (Wi-LAN Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Arnaud, Thierry, Khlat, Nadmi
• Primary Examiner(s): Tso, Edward H.
• Assistant Examiner(s): TOATLEY, GREGORY J
• Application Number:
  US09/297,485
• Time in Patent Office: 767 Days
• Field of Search: 320/135, 320/136, 320/103, 307/48, 307/66
• US Class Current: 320/135
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/0063 with circuits adapted for supplying loads from the battery
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H04B 1/3883 Arrangements for mounting batteries or battery chargers

Abstract

A portable electronic device such as a mobile telephone is powered by a battery and is arranged to operate in an off-mode, a standby mode and an on-mode of operation. Primary electronic circuitry, operable only during the on-mode, provides the main features of the device. Secondary electronic circuitry is operable during the off-mode, and standby circuitry is operable during the standby mode. A power supply circuit is arranged for coupling to the battery in order to provide power to the electronic device during the on-mode. A secondary power source is arranged to be charged by the power supply circuit during the on-mode and further arranged for providing power to the second electronic circuitry during the off-mode. The secondary power source is further arranged for providing power to the standby circuitry during the standby mode, such that the power supply circuit does not operate during the standby mode.

Claims

1. A portable electronic device, arranged to be powered by a battery and to operate in an off-mode, a standby mode and an on-mode of operation, comprising:

primary electronic circuitry, operable only during the on-mode;

secondary electronic circuitry operable during the off-mode;

standby circuitry operable during the standby mode;

a power supply circuit, arranged for coupling to the battery in order to provide power to the electronic device during the on-mode;

a secondary power source, arranged to be charged by the power supply circuit during the on-mode and further arranged for providing power to the second electronic circuitry during the off-mode,

wherein the secondary power source is further arranged for providing power to the standby circuitry during the standby mode, such that the power supply circuit does not operate during the standby mode.

2. The portable electronic device of claim 1, further comprising a trickle-charge circuit arranged to charge the secondary power source during the on-mode.

3. The portable electronic device of claim 1 or claim 2, further comprising a switch arranged to selectively couple one of the power supply circuit and the secondary power source in order to provide power to the standby circuitry.

4. A method of operating a portable electronic device arranged to be powered by a battery and having primary electronic circuitry arranged only to operate in an on-mode, standby circuitry arranged to operate in a standby mode and secondary electronic circuitry arranged to operate in an off-mode of operation, comprising the steps of:

providing power to the primary electronic circuitry during the on-mode via a power supply circuit coupled to the battery;

charging a secondary power source during the on-mode;

providing power to secondary electronic circuitry during the off-mode via the secondary power source;

providing power to the standby circuitry during the standby mode via the secondary power source, such that the power supply circuit does not operate during the standby mode.

5. The method of claim 4 further including the step of using a real-time clock in the secondary electronic circuitry.

6. The method of claim 4 further including the step of using a button cell for the secondary power source.

7. The method of claim 4 further including the step of using the primary electronic circuitry for providing main operating features of the device.

8. The method of claim 4 further including the step of including a microprocessor in the primary electronic circuitry.

9. The method of claim 4 further including the step of using the standby circuitry for monitoring the secondary power source during the standby mode and enabling the power supply circuit when the secondary power source falls below a predetermined voltage level.

10. The method of claim 4 further including the step of using the portable electronic device in a mobile telephone.