CA2344753C - Method for extending the useful life of a cordless telephone backup battery during a power outage condition - Google Patents
Method for extending the useful life of a cordless telephone backup battery during a power outage condition Download PDFInfo
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- CA2344753C CA2344753C CA002344753A CA2344753A CA2344753C CA 2344753 C CA2344753 C CA 2344753C CA 002344753 A CA002344753 A CA 002344753A CA 2344753 A CA2344753 A CA 2344753A CA 2344753 C CA2344753 C CA 2344753C
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- base unit
- cndot
- cordless telephone
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- telephone system
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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Abstract
The disclosure discloses a method for extending the length of time over which a cordless telephone system can operate without an external source of power. The method involves detecting a power supply outage, determining that a telephone call is not currently being handled, placing the portable unit into a mode of reduced power consumption, and placing the base unit into s mode of reduced power consumption. After a period of time, the base unit resumes functionality, determines whether a call is being initiated, and handles any such calls. If the system is not active, the base unit re-enters its mode of reduced power consumption, and tile cycle is repeated.
Description
TITLE OF THE INVENTIC)N
Method For Extending The Usefu! Life Of A Cordless Telephone Backup Battery During A Power Outage Condition BACKGROUND OF THE INVENTION
Cordless telephones have become a common fixture in the modern household, to the extent that many consumers now have few, if any, conventional corded telephones. While the convenience, mobility, and high sound quality of cordless 1 Q telephones have attracted many consumers, one of their drawbacks is that they consume more power than can be provided by a conventional telephone tine.
Consequently, modern cordless telephones must be plugged infio a power outlet for operatior.~.
One significant drawback of wail-powered cordless telephones is that such telephones commonly become inoperative during a power outage. If the telephone consumer does not also own a conventional corded telephone that operates on telephone line power, the consumer is then unable to place a telephone call reporting the power outage, or otf~er emergencies. As a result, consumers must either keep an unwanted conventional telephone in service, or risk elimination of telephone services in the event o. a power o~itage. Even if a consumer does keep a corded telephone in service, they will be inc~cnvenienced by having to locate and utilize the corded telephone while power is out.
Some prior art cordless telephone designs have addressed this problem by including a rechargeable battery pack in the cordless telephone base unit, which can temporarily provide power to the base unit when the wall power supply fails, However, the effectiveness of this solution is limited by the significant power consumption of a typical cordless telephony system, resulting in limited battery life.
It i: therefore an object of this invention to maximize cordless telephone utilization dime following .a power outage by placing the system into a sleep mode, during which power con~~umption is reduced.
It is another object of this invention to periodically check for incoming or outgoing calls such that the syste« retains functionality during the power outage.
It is yet another object of this invention to control the frequency,with which the 'l Q system checks for calf a~~ivity based upon the power Level remaining in the rechargeable batteries.
SUMMARY OF THE IN'JENTION
The invention involves a cordless telephone system, including a base unit and a portable .unit, each capable of operating from a rechargeable battery pack as a power source. The base unit is further capable of operating on power supplied by an external source, :such as a wall outlet and AC-to-DC converter.
In accordance with the method of the invention, the base unit detects when the extemat~source of pow~:~r fails. If the telephone system is not currently handling a call, the portable unit is placed into a mode in which its power consumption is reduced. The base unit is also places.( into a mode of reduce power consumption, during which time calls cannot be proces >ed. The length of the sleep period can be fixed at a predetermined interval. Alternatively, the period length can vary based on the amount of power remaining in the base unit battery. fn one embodiment, the sleep period is interrupted immediately upon receipt of an incoming call on the telephone fine to which the base unit is connected.
After sleeping for ~.~ period of time, the base unit circuits are awakened.
The base unit,then determines whether the telephone system is active. The telephone system will be deemed active if, for example, a telephone caI! is being placed by a user of the handset, or an incoming cal! is being received on the telephone line into which the base unit is connected. l~ the telephone system is active, the base unit handles the call.
Fimahy, when the telephone system is not active, and power is still not being 'l 0 supplied by the external power source, the base unit is placed back into the state of reduced power consumrtion, and the cycle is repeated.
BRIEF DESCRIPTION ~:JF THE DRAWf(~CS
Figure 1 of the drawings is a schematic diagram of one embodiment of the '! 5 invention.
Figure 2 of the drawings is a flowchart describing the operation of one embodiment of the invention.
Method For Extending The Usefu! Life Of A Cordless Telephone Backup Battery During A Power Outage Condition BACKGROUND OF THE INVENTION
Cordless telephones have become a common fixture in the modern household, to the extent that many consumers now have few, if any, conventional corded telephones. While the convenience, mobility, and high sound quality of cordless 1 Q telephones have attracted many consumers, one of their drawbacks is that they consume more power than can be provided by a conventional telephone tine.
Consequently, modern cordless telephones must be plugged infio a power outlet for operatior.~.
One significant drawback of wail-powered cordless telephones is that such telephones commonly become inoperative during a power outage. If the telephone consumer does not also own a conventional corded telephone that operates on telephone line power, the consumer is then unable to place a telephone call reporting the power outage, or otf~er emergencies. As a result, consumers must either keep an unwanted conventional telephone in service, or risk elimination of telephone services in the event o. a power o~itage. Even if a consumer does keep a corded telephone in service, they will be inc~cnvenienced by having to locate and utilize the corded telephone while power is out.
Some prior art cordless telephone designs have addressed this problem by including a rechargeable battery pack in the cordless telephone base unit, which can temporarily provide power to the base unit when the wall power supply fails, However, the effectiveness of this solution is limited by the significant power consumption of a typical cordless telephony system, resulting in limited battery life.
It i: therefore an object of this invention to maximize cordless telephone utilization dime following .a power outage by placing the system into a sleep mode, during which power con~~umption is reduced.
It is another object of this invention to periodically check for incoming or outgoing calls such that the syste« retains functionality during the power outage.
It is yet another object of this invention to control the frequency,with which the 'l Q system checks for calf a~~ivity based upon the power Level remaining in the rechargeable batteries.
SUMMARY OF THE IN'JENTION
The invention involves a cordless telephone system, including a base unit and a portable .unit, each capable of operating from a rechargeable battery pack as a power source. The base unit is further capable of operating on power supplied by an external source, :such as a wall outlet and AC-to-DC converter.
In accordance with the method of the invention, the base unit detects when the extemat~source of pow~:~r fails. If the telephone system is not currently handling a call, the portable unit is placed into a mode in which its power consumption is reduced. The base unit is also places.( into a mode of reduce power consumption, during which time calls cannot be proces >ed. The length of the sleep period can be fixed at a predetermined interval. Alternatively, the period length can vary based on the amount of power remaining in the base unit battery. fn one embodiment, the sleep period is interrupted immediately upon receipt of an incoming call on the telephone fine to which the base unit is connected.
After sleeping for ~.~ period of time, the base unit circuits are awakened.
The base unit,then determines whether the telephone system is active. The telephone system will be deemed active if, for example, a telephone caI! is being placed by a user of the handset, or an incoming cal! is being received on the telephone line into which the base unit is connected. l~ the telephone system is active, the base unit handles the call.
Fimahy, when the telephone system is not active, and power is still not being 'l 0 supplied by the external power source, the base unit is placed back into the state of reduced power consumrtion, and the cycle is repeated.
BRIEF DESCRIPTION ~:JF THE DRAWf(~CS
Figure 1 of the drawings is a schematic diagram of one embodiment of the '! 5 invention.
Figure 2 of the drawings is a flowchart describing the operation of one embodiment of the invention.
~ETAtLEC~ DESCRfPTIO!~ OF THE INVENTION
While this invention is susceptible to embodiment in many forms, there is shown in the drawings and will herein be described in detail specific embodiments, with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to embodiments illustrated, The present invention comprises a method and apparatus for extending the duration over which a cordless telephone can operate after its external power source has faiied. The inventio~~ places both the base unit and portable unit of the cordless '10 telephone into a low-povaer mode while inactive and operating on battery power.
In the ernbodimeot of Figure 1, a primary externs( power source is applied to the base unit at the external power source input, Vunreg. in this embodiment, approxin~sately +9VDC i:; applied to Vunreg, typically converted from a wall outset AC
voltage by an AC-to-DG converter, which can be either internal to the base unit or 'i 5 external. During nom~a~~ operation, regulator U1 converts the Vunreg voltage level to +5 VDG. Regulator U2 then regulates the voltage level down to +3 VDG for distribution to the remaining active components in the base unit.
T'.;~e external po~rver source also charges batteries B1 and B2. Base unit battery B1 is charged through ~.;urrent limiting resistor R1 and diode D1. Diode D1 prevents the 20 reverse flow of current fram battery B1 to Vunreg in the event of a failure of the primary power source, The external power source charges portable unit battery B2 when the portable unit is electrically engaged with the base unit. Current flows from Vunreg, through~diode D2 and ~;;urrent limiting resistor R6, into B2. Diode D2 prevents the reverse flow of current from battery B2 to Vunreg in the event of a failure of the primary power source.
Cornparator U4, ir~ combination with resistors R7, R6, R9, and R10, detects failure of the primary pov~,~er source by comparing the Vunreg voltage to the voltage at battery B'., . When the primary power source fails, the output of U4 transitions from high to iow. The state of the ~:omparator U4 output is detected by microcontroller U3.
Transistors Q1, D 2, and Q3, along with resistors R2, R3, R4, and R5, form a power sv~itch circuit which automatically provides power to the base unit circuitry from Vunreg when Vunreg is present; and from battery B1, if Vunreg fails. As was stated, during normal operation Vunreg supplies current to regulators U1 and U2 for distFibution to the base unit circuitry. Vunreg also biases resistors R2 and R3, turning on transistor Q3. Q3 1?ulls the base of Q2 low, thereby turning Q2 off. When Q2 is off, it draws no current from the base ov' Q1, thereby turning transistor Q1 off. Because Q1 is ofd, the battery B1 is disconnected from the rest of the circuitry during normal operation.
When Vunreg fails, Q3 is turned off. Battery B1 biases the base of Q2, causing Q2 to turn on Q1. Therefore, current flows from battery B1 through transistor C~'i , far regulation by U2 and subsequent distribution to the base unit circuitry 100.
The embodiment of f=igure 1 further includes circuitry for charging the battery of the portable unit when the portable unit and the base unit are engaged and the prirt~ary power source has faile~~. If battery B2 nears depletion while base unit battery l31 has power remaining, microcontroller U3 can temporarily close switch SW1 to transfer energy between batteries B1 and B2 through current-limiting resistor R11.
The: operation of the invention when the primary power source has failed is explained in the flow chaff t of Figure 2, When the primary power source fails and a call is not in progress, step 10, the base unit sends a sleep command to the handset, step 'i 1. The base unit then ~~laces its own circuitry into a sleep mode in step 12. The sleep mode constitutes a model of operation in which power consumption is decreased, while the functionality of many circuits is suspended or reduced. In the preferred embodiment, the transmitter and receiver circuits are powered off.
Microcontroifers are either placed into a steady state, or operated with clock freguencies reduced from, for example, 8 MHz to 32 kr~z. .When a devices awakens from a sleep mode, its circuits typically resume their vormal functionality.
During the steep mode, both the base unit and the portable unit awaken periodically. (n one emhodiment, each unit awakens once every 1.5 seconds. The precise ti'rne between awakenings can be varied to suit particular design goats. As the period increases, energy use is reduced, but unit responsiveness is also reduced, forcing a user to wait a:~ much as a full period before the handset responds to an incoming call, or the base responds to the user's attempt to initiate a calf.
in another embodiment, the period varies in accordance with the level of energy remaining in the backup ioattery. While she battery is highly charged, the sleep period may be comparatively short, such as .5 seconds, thereby providing a high level of 2~ responsiveness to the user during shorter power outages. As the battery charge falls, the period between awakenings increases to avoid complete operation outage.
in step 13, the vase unit starts a timer during which duration the base ur~4t circuits remain in sleep mode. An interrupt is provided by step 14, such that if the bass detects an incoming telephone ca.Ul on the telephone line to which the base unit is connected, the base unit circuits are awoken immediately, step 18, and the call is handled, step 19.
athervvise, after the timer has completed its duration, step 15, the tease unit circuits are awoken ira step 16.
WElen the base ur~if awakens from the power-conserving mode of operation, its receiver scans for radio ~:ransmissions emanating from the portable unit which would indicate that the portable unit is initiating a telephone call, or engaging in some other communication which reguires base unit participation. Similarly, when the portabie unit awakens, its receiver scans for radio transmissions emanating from the base unit that '10 would indicate a teiephc~ne. call is being received. 'his steep mode operation of the porfiable unit may differ ~drom conventional power-consenting handset operation in that the time period between awakenings can be increased from the typical .5 seconds or less to match the base unit and further reduce power consumption.
In step 17, the base unit receiver then scans for radio transmissions emanating 'E 5 from the:portabfe unit which would indicate that the portable unit is paging the base unit to initiate a telephone calf, or engaging in some other communication which reguires base unit participation, such as an intercom connection. if the base unit detects paging by the handset, the base unit handles the calf, step 'f 8. If the base unit does nvt detect any paging by the handset in step 'f7, the base unit returns to the start of the power-2D failure operation cycle ~.>f Figure 2.
'T'he foregoing d~:acriptions and drawings merely explain and illustrate the invention and the invention is not Vimited thereto except insofar as the appended claims are so limited, as those; skilled in the art who have the disclosure before them will be at~fe to make modificatiorss or variations therein without departing firom the scope of the invention.
While this invention is susceptible to embodiment in many forms, there is shown in the drawings and will herein be described in detail specific embodiments, with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to embodiments illustrated, The present invention comprises a method and apparatus for extending the duration over which a cordless telephone can operate after its external power source has faiied. The inventio~~ places both the base unit and portable unit of the cordless '10 telephone into a low-povaer mode while inactive and operating on battery power.
In the ernbodimeot of Figure 1, a primary externs( power source is applied to the base unit at the external power source input, Vunreg. in this embodiment, approxin~sately +9VDC i:; applied to Vunreg, typically converted from a wall outset AC
voltage by an AC-to-DG converter, which can be either internal to the base unit or 'i 5 external. During nom~a~~ operation, regulator U1 converts the Vunreg voltage level to +5 VDG. Regulator U2 then regulates the voltage level down to +3 VDG for distribution to the remaining active components in the base unit.
T'.;~e external po~rver source also charges batteries B1 and B2. Base unit battery B1 is charged through ~.;urrent limiting resistor R1 and diode D1. Diode D1 prevents the 20 reverse flow of current fram battery B1 to Vunreg in the event of a failure of the primary power source, The external power source charges portable unit battery B2 when the portable unit is electrically engaged with the base unit. Current flows from Vunreg, through~diode D2 and ~;;urrent limiting resistor R6, into B2. Diode D2 prevents the reverse flow of current from battery B2 to Vunreg in the event of a failure of the primary power source.
Cornparator U4, ir~ combination with resistors R7, R6, R9, and R10, detects failure of the primary pov~,~er source by comparing the Vunreg voltage to the voltage at battery B'., . When the primary power source fails, the output of U4 transitions from high to iow. The state of the ~:omparator U4 output is detected by microcontroller U3.
Transistors Q1, D 2, and Q3, along with resistors R2, R3, R4, and R5, form a power sv~itch circuit which automatically provides power to the base unit circuitry from Vunreg when Vunreg is present; and from battery B1, if Vunreg fails. As was stated, during normal operation Vunreg supplies current to regulators U1 and U2 for distFibution to the base unit circuitry. Vunreg also biases resistors R2 and R3, turning on transistor Q3. Q3 1?ulls the base of Q2 low, thereby turning Q2 off. When Q2 is off, it draws no current from the base ov' Q1, thereby turning transistor Q1 off. Because Q1 is ofd, the battery B1 is disconnected from the rest of the circuitry during normal operation.
When Vunreg fails, Q3 is turned off. Battery B1 biases the base of Q2, causing Q2 to turn on Q1. Therefore, current flows from battery B1 through transistor C~'i , far regulation by U2 and subsequent distribution to the base unit circuitry 100.
The embodiment of f=igure 1 further includes circuitry for charging the battery of the portable unit when the portable unit and the base unit are engaged and the prirt~ary power source has faile~~. If battery B2 nears depletion while base unit battery l31 has power remaining, microcontroller U3 can temporarily close switch SW1 to transfer energy between batteries B1 and B2 through current-limiting resistor R11.
The: operation of the invention when the primary power source has failed is explained in the flow chaff t of Figure 2, When the primary power source fails and a call is not in progress, step 10, the base unit sends a sleep command to the handset, step 'i 1. The base unit then ~~laces its own circuitry into a sleep mode in step 12. The sleep mode constitutes a model of operation in which power consumption is decreased, while the functionality of many circuits is suspended or reduced. In the preferred embodiment, the transmitter and receiver circuits are powered off.
Microcontroifers are either placed into a steady state, or operated with clock freguencies reduced from, for example, 8 MHz to 32 kr~z. .When a devices awakens from a sleep mode, its circuits typically resume their vormal functionality.
During the steep mode, both the base unit and the portable unit awaken periodically. (n one emhodiment, each unit awakens once every 1.5 seconds. The precise ti'rne between awakenings can be varied to suit particular design goats. As the period increases, energy use is reduced, but unit responsiveness is also reduced, forcing a user to wait a:~ much as a full period before the handset responds to an incoming call, or the base responds to the user's attempt to initiate a calf.
in another embodiment, the period varies in accordance with the level of energy remaining in the backup ioattery. While she battery is highly charged, the sleep period may be comparatively short, such as .5 seconds, thereby providing a high level of 2~ responsiveness to the user during shorter power outages. As the battery charge falls, the period between awakenings increases to avoid complete operation outage.
in step 13, the vase unit starts a timer during which duration the base ur~4t circuits remain in sleep mode. An interrupt is provided by step 14, such that if the bass detects an incoming telephone ca.Ul on the telephone line to which the base unit is connected, the base unit circuits are awoken immediately, step 18, and the call is handled, step 19.
athervvise, after the timer has completed its duration, step 15, the tease unit circuits are awoken ira step 16.
WElen the base ur~if awakens from the power-conserving mode of operation, its receiver scans for radio ~:ransmissions emanating from the portable unit which would indicate that the portable unit is initiating a telephone call, or engaging in some other communication which reguires base unit participation. Similarly, when the portabie unit awakens, its receiver scans for radio transmissions emanating from the base unit that '10 would indicate a teiephc~ne. call is being received. 'his steep mode operation of the porfiable unit may differ ~drom conventional power-consenting handset operation in that the time period between awakenings can be increased from the typical .5 seconds or less to match the base unit and further reduce power consumption.
In step 17, the base unit receiver then scans for radio transmissions emanating 'E 5 from the:portabfe unit which would indicate that the portable unit is paging the base unit to initiate a telephone calf, or engaging in some other communication which reguires base unit participation, such as an intercom connection. if the base unit detects paging by the handset, the base unit handles the calf, step 'f 8. If the base unit does nvt detect any paging by the handset in step 'f7, the base unit returns to the start of the power-2D failure operation cycle ~.>f Figure 2.
'T'he foregoing d~:acriptions and drawings merely explain and illustrate the invention and the invention is not Vimited thereto except insofar as the appended claims are so limited, as those; skilled in the art who have the disclosure before them will be at~fe to make modificatiorss or variations therein without departing firom the scope of the invention.
Claims (6)
1. A method for extending the duration over which a cordless telephone system can operate without an external source of power, which telephone system includes a base unit with a transmitter, receiver, and first backup battery pack, and a portable unit with a transmitter, receiver, and second backup battery pack, the method comprising the following steps:
.cndot. determining that power is not being supplied to the base unit from an external source;
.cndot. determining that a telephone call is not being handed by the cordless telephone system;
.cndot. sending a sleep command to the portable unit if the external power supply is absent and a telephone call is not being handled;
.cndot. placing the base unit into a state of reduced power consumption;
.cndot. pausing for a period of time;
.cndot. ceasing operation in the state of reduced power consumption;
.cndot. determining whether the cordless telephone system is active;
.cndot. placing the base unit back into a sleep mode when the cordless telephone system is not active and power is not being supplied to the base unit from an external power source,
.cndot. determining that power is not being supplied to the base unit from an external source;
.cndot. determining that a telephone call is not being handed by the cordless telephone system;
.cndot. sending a sleep command to the portable unit if the external power supply is absent and a telephone call is not being handled;
.cndot. placing the base unit into a state of reduced power consumption;
.cndot. pausing for a period of time;
.cndot. ceasing operation in the state of reduced power consumption;
.cndot. determining whether the cordless telephone system is active;
.cndot. placing the base unit back into a sleep mode when the cordless telephone system is not active and power is not being supplied to the base unit from an external power source,
2. The method of claim 1, in which the step of pausing for a period of time is terminated immediately if an incoming call is detected on the telephone line to which the base unit is connected.
3. The method of claim 1, in which the step of pausing for a period of time is comprised of the following substeps:
.cndot. determining the level of power remaining in the first backup battery;
.cndot. pausing for a period of time corresponding to the level of power remaining in the first backup battery.
.cndot. determining the level of power remaining in the first backup battery;
.cndot. pausing for a period of time corresponding to the level of power remaining in the first backup battery.
4. The method of claim 3, in which the period of time over which the base unit pauses in a steep mode increases as the energy level remaining in the first backup battery decreases.
5. The method of claim 1, in which the step of determining whether the cordless telephone system is active comprises the substeps of:
.cndot. scanning with the base unit receiver for signals transmitted by the portable unit;
.cndot. determining that the cordless telephone system is active if the base unit detects a signal transmitted by the portable unit.
.cndot. scanning with the base unit receiver for signals transmitted by the portable unit;
.cndot. determining that the cordless telephone system is active if the base unit detects a signal transmitted by the portable unit.
6. The method of claim 1, in which the step of determining whether the cordless telephone system is active comprises the substeps of:
.cndot. scanning with the base unit receiver for signals transmitted by the portable unit;
.cndot. detecting whether or not a telephone call is being received on the telephone line to which the base unit is connected;
.cndot. determining that the cordless telephone system is active if the base unit detects a signal transmitted by the portable unit or a telephone call on the telephone line.
.cndot. scanning with the base unit receiver for signals transmitted by the portable unit;
.cndot. detecting whether or not a telephone call is being received on the telephone line to which the base unit is connected;
.cndot. determining that the cordless telephone system is active if the base unit detects a signal transmitted by the portable unit or a telephone call on the telephone line.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US09/557,692 | 2000-04-25 | ||
| US09/557,692 US6271472B1 (en) | 1999-04-15 | 2000-04-25 | Ultra thin and flexible SCSI cable and method for making same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2344753A1 CA2344753A1 (en) | 2001-10-25 |
| CA2344753C true CA2344753C (en) | 2004-09-21 |
Family
ID=24226500
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002344753A Expired - Fee Related CA2344753C (en) | 2000-04-25 | 2001-04-24 | Method for extending the useful life of a cordless telephone backup battery during a power outage condition |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2344753C (en) |
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2001
- 2001-04-24 CA CA002344753A patent/CA2344753C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CA2344753A1 (en) | 2001-10-25 |
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