Portable wireless telephone apparatus with use specific power monitoring

• US 5,392,462 A
• Filed: 09/17/1992
• Issued: 02/21/1995
• Est. Priority Date: 09/27/1991
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Komaki, Norio
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): PHAM, CHI H
• Application Number:
  US07/945,874
• Time in Patent Office: 887 Days
• Field of Search: 455/89, 455/95, 455/127, 455/343, 455/351, 455/33.1, 379/58, 379/61, 379/59
• US Class Current: 455/552.1
• CPC Class Codes: H04W 52/0277 according to available power supply, e.g. switching off when a low battery condition is detected
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

In a portable wireless telephone capable of providing a cellular mode which allows users to place or receive telephone calls through a cellular telephone network and a cordless mode which allows the users to place or receive telephone calls through an associated base unit of a cordless telephone, a battery voltage is monitored to check whether or not the battery voltage is so lowered that the cellular mode becomes inoperative. An LCD unit displays a low-voltage warning if the battery voltage is lowered down to such a low level. However, a micro computer equipped in this portable wireless telephone allows the users to use this portable wireless telephone as a cordless telephone. Accordingly, this portable wireless telephone can be still activated in the cordless mode even if it cannot be no longer used as a cellular telephone.

Claims

1. A portable wireless telephone comprising:

an antenna;

a cellular transmit/receive means connected to said antenna for transmitting data to or receiving data from a cellular base station;

a cordless transmit/receive means connected to said antenna for transmitting data to or receiving data from a base unit of a cordless telephone;

a mode selecting means for selecting an operation mode of the portable wireless telephone between a cellular mode and a cordless mode;

a battery;

a voltage detecting means connected to said battery for generating a low-voltage signal if a battery voltage is not large enough to operate the portable wireless telephone in the cellular mode;

a display means;

a control means for controlling said display means to generate a low-voltage warning, which indicates that the cellular mode is no longer operative, whenever said voltage detecting means generates the low-voltage signal when the portable wireless telephone is operated in the cellular mode, and for further controlling said mode selecting means to prevent selection of the cellular mode while permitting selection of the cordless mode as long as said battery voltage is large enough to operate the portable wireless telephone in the cordless mode.

2. A portable wireless telephone comprising:

an antenna;

a cellular transmit/receive means connected to said antenna for transmitting data to or receiving data from a cellular base station;

a cordless transmit/receive means connected to said antenna for transmitting data to or receiving data from a base unit of a cordless telephone;

a mode selecting means for selecting an operation mode of the portable wireless telephone between a cellular mode and a cordless mode;

a battery;

a first voltage detecting means connected to said battery for generating a first low-voltage signal if a battery voltage is not large enough to activate the portable wireless telephone as a cellular telephone;

a second voltage detecting means connected to said battery for generating a second low-voltage signal if the battery voltage is not large enough to activate the portable wireless telephone as a cordless telephone;

a display means; and

a control means wherein said control means controls said display means to generate a first low-voltage warning, which indicates that only the cellular mode is no longer operative, whenever said first voltage detecting means generates the first low-voltage signal, and further controls said display means to generate a second low-voltage warning, which indicates that all the modes are no longer operative, whenever said second voltage detecting means generates the second low voltage signal.

3. A portable wireless telephone in accordance with claim 2 in which said control means further controls said mode selecting means not to select the cellular mode in response to a detection of said first low-voltage signal.

4. A portable wireless telephone in accordance with claim 2 in which said control means further controls said mode selecting means not to select the cordless mode in response to a detection of said second low-voltage signal.

5. A portable wireless telephone comprising:

an antenna;

a cellular transmit/receive means connected to said antenna for transmitting data to or receiving data from a cellular base station;

a cordless transmit/receive means connected to said antenna for transmitting data to or receiving data from a base unit of a cordless telephone;

a mode selecting means for selecting an operation mode of the portable wireless telephone between a cellular mode and a cordless mode;

a battery;

a micro computer accommodating an A/D converter and memorizing a first minimum battery voltage required for activating the portable wireless telephone as a cellular telephone and a second minimum battery voltage required for activating the portable wireless telephone as a cordless telephone, so that the minimum battery voltage values can be used as reference values when checking a remaining voltage of the battery;

a display means; and

wherein said micro computer causes said A/D converter to transform the remaining battery voltage into a digital value and compares the remaining battery voltage value which is A/D transformed in the A/D converter with said first minimum battery voltage, so that said micro computer controls the display means to generate a warning of a low-voltage as a cellular mode if the remaining battery voltage is lower than the first minimum battery voltage, and further comparing the remaining battery voltage value which is A/D transformed in the A/D converter with said second minimum voltage, so that said micro computer controls the display means to generate a warning of a low-voltage as both cellular and cordless modes if the remaining battery voltage is lower than the second minimum battery voltage.

6. A portable wireless telephone in accordance with claim 5 in which said micro computer further controls said mode selecting means not to select the cellular mode when the remaining battery voltage is lower than the first minimum battery voltage.

7. A portable wireless telephone in accordance with claim 5 in which said micro computer further controls said mode selecting means not to select the cordless mode when the remaining battery voltage is lower than the second minimum battery voltage.