(12) United States Patent
`Marmaropoulos et al.
`
`USOO6462437B1
`(10) Patent No.:
`US 6,462,437 B1
`(45) Date of Patent:
`Oct. 8, 2002
`
`(54) SYSTEM AND METHOD FOR
`ALTERNATING STANDBY MODE
`
`(75) Inventors: George Marmaropoulos, Yorktown
`to they's Briarcliff
`s
`(73) Assignee: Koninklijke Philips Electronics N.V.,
`Eindhoven (NL)
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`
`(*) Notice:
`
`5,689.407 A * 11/1997 Marinus et al. .......... 363/21.12
`5,812,383 A * 9/1998 Majid et al. .................. 363/21
`5,852,550 A * 12/1998 Majid et al. ...
`... 363/21
`E. A : g ME - - - -
`- - - 35
`2Y----Y-2
`:
`ald el al. . . . . . . . . . . . . . . . . . .
`6,157,549 A 12/2000 Nath .......................... 348/730
`6,188,587 B1
`2/2001 Yun et al. ..................... 363/21
`6,191.959 B1
`2/2001 Miermans .................... 363/21
`FOREIGN PATENT DOCUMENTS
`2000-224844
`JP
`* 11/2000
`* cited by examiner
`Primary Examiner Fritz Fleming
`ASSistant Examiner Roberto J. Rios
`(74) Attorney, Agent, or Firm-Dicran Halajian
`(57)
`ABSTRACT
`
`21 Ap1. No.: 09/439,195
`(21) Appl. No.: 09/439,
`(22) Filed:
`Nov. 12, 1999
`(51) Int. Cl." ............................................... H02M 3/335
`(52) U.S. Cl. ................
`... 307/125; 348/730; 363/21
`(58) Field of Search
`s
`307125 140
`307/38; 363/21, 49; 348/730
`References Cited
`
`(56)
`
`An apparatus and method for reducing the level of power
`pp
`9.
`p
`consumption in an electronic device when the electronic
`device is operating in a standby mode or low-power mode.
`The level of power consumption is reduced by alternately
`Shutting off Standby power and turning on Standby power to
`the electronic device. A Standby cycle timer circuit is pro
`Vided for automatically controlling the Supply of Standby
`U.S. PATENT DOCUMENTS
`power to the electronic device during Standby mode. The
`4,688,159 A
`8/1987 Marinus ...................... if standbv cvcle timer circuit becomes inactive when the
`y cycle
`4,868,662 A * 9/1989 Hartman et al. .....
`... 31.5/411
`4,975,592 A * 12/1990 Hahn et al. ................... 30738
`electronic device resumes normal operation.
`5,381,329 A * 1/1995 Koblitz et al. ................ 363/49
`5,477,279 A * 12/1995 Chang ........................ 348/730
`
`26 Claims, 4 Drawing Sheets
`
`
`
`supply
`
`3) -
`
`- -
`
`sta wid,y
`cycle
`mer
`
`C/s Tawpay
`
`32 () ---
`
`
`
`
`
`
`
`
`
`
`
`Fows
`Supply
`2.)
`
`VIZIO, Inc. Exhibit 1009
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 1 of 11
`
`

`

`U.S. Patent
`
`Oct. 8, 2002
`
`Sheet 1 of 4
`
`US 6,462,437 B1
`
`
`
`W/Md
`
`VIZIO, Inc. Exhibit 1009
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 2 of 11
`
`

`

`U.S. Patent
`
`Oct. 8, 2002
`
`Sheet 2 of 4
`
`US 6,462,437 B1
`
`VIZIO, Inc. Exhibit 1009
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 3 of 11
`
`

`

`U.S. Patent
`
`US 6,462,437 B1
`
`
`
`(C)
`QD
`|-
`L
`
`
`
`
`
`||TT-(\W|\W|| Loulao waea
`
`VIZIO, Inc. Exhibit 1009
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 4 of 11
`
`

`

`U.S. Patent
`
`Oct. 8, 2002
`
`Sheet 4 of 4
`
`US 6,462,437 B1
`
`ya
`
`-s/ SOO
`
`MO
`
`TLRAV ow
`STA MV Day
`Powe &
`
`were
`SiO
`
`5HuT Edway S2O
`AODA Fog
`dAvé CYCLE
`
`stawpsy
`mo De For --53O
`OME Cyat E
`
`A/O
`
`5 H-O
`
`yeS
`
`
`
`AV (9 RM1. A
`ope RA-Trave
`Pawe R
`
`540
`
`F1 G. H.
`
`VIZIO, Inc. Exhibit 1009
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 5 of 11
`
`

`

`1
`SYSTEMAND METHOD FOR
`ALTERNATING STANDBY MODE
`
`TECHNICAL FIELD OF THE INVENTION
`The present invention is directed, in general, to electronic
`devices and, more specifically, to an apparatus and method
`for reducing the level of power consumption in an electronic
`device when the electronic device is operating in a Standby
`mode or low-power mode.
`
`BACKGROUND OF THE INVENTION
`In electronic devices it is Sometimes desirable to operate
`the device in a standby mode (also called a low-power
`mode) rather than to turn off all power to the device when
`the device is not in use. For example, in a television Set it is
`customary to continually Supply power to the heating ele
`ments of the electronic circuitry even when the Set is
`otherwise turned off. This permits the electronic circuitry
`that operates the various components of the television Set
`(e.g., circuitry that operates the cathode ray tube of the
`television Screen) to very quickly achieve the proper level of
`operation when the Set is turned on. If one did not keep the
`set minimally powered in a standby mode it would be
`necessary to wait for the heating elements of the Set to warm
`up when the Set was turned on.
`Therefore, it is desirable and useful to use the standby
`mode in electronic devices Such as radio Sets, television Sets,
`Stereo sets, and other Similar types of electronic devices. The
`amount of energy that is consumed when an electronic
`device is in Standby mode is Small in comparison to the
`amount of power that the electronic device uses when the Set
`is turned on. However, because the use of standby mode in
`electronic devices is So widespread and because the use of
`Standby mode does consume electric power, the power that
`is consumed by Standby mode in the aggregate is quite large.
`To realize the magnitude of the aggregate power consump
`tion due to use of the Standby mode, one may multiply the
`Small amount of power consumed in one television Set that
`is operating in Standby mode by the millions of television
`sets that exist in the world today.
`Certain improvements in electronic design within the last
`few years have reduced the amount of power consumption
`that is due to the operation of Standby mode circuitry.
`Because the aggregate amount of Standby mode power
`consumption is still quite large, however, there still remains
`a need to find additional ways to further reduce the level of
`Standby mode power consumption in electronic devices.
`
`SUMMARY OF THE INVENTION
`To address this problem, it is a primary object of the
`present invention to provide an apparatus and method for
`reducing the level of power consumption in an electronic
`device that is operating in Standby mode.
`It is a further object of the present invention to provide a
`means for reducing the amount of power consumption in an
`electronic device that is operating in Standby mode by at
`least fifty percent.
`The apparatus and method of the present invention will be
`described as an apparatus and method for reducing the level
`of power consumption in a television Set that is operating in
`a Standby power mode. It is important to realize that the
`apparatus and method of the present invention is not limited
`to only a television set. Those skilled in the art will readily
`understand that the principles of the present invention may
`also be Successfully applied to other types of electronic
`
`15
`
`25
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`US 6,462.437 B1
`
`2
`devices. However, in the descriptions that follow, a televi
`Sion Set is employed for illustration purposes
`In the preferred embodiment of the invention, the inven
`tion comprises a Standby cycle timer circuit coupled within
`a television power Supply circuit capable of operating in a
`Standby mode. The Standby cycle timer causes the power
`Supply circuit to alternate between its Standard Standby
`mode and a shutdown power mode. In a shutdown power
`mode, all power from the power Supply circuit to other
`circuit elements is turned off. After a predetermined period
`of time has elapsed, the shutdown power mode is terminated
`and the Standby power mode is resumed. After another
`predetermined period of time has elapsed, the Standby power
`mode is terminated and the shutdown power mode is
`resumed. The alternation of the standby power mode and the
`shutdown power mode continues until the television
`receives an “on” Signal to power up the television for normal
`operation.
`If the time that the shutdown power mode is in operation
`is equal to the time that the Standby power mode is in
`operation, then the power consumption of the combination
`is half of the power consumption required to otherwise
`operate in only the standby power mode. If the time that the
`shutdown power mode is in operation is greater than the time
`that the Standby power mode is in operation, then the power
`consumption of the combination will be less than half of the
`power consumption required to otherwise operate in only the
`Standby power mode. Therefore, the invention provides a
`Significant reduction in the amount of power needed to
`operate a television in a Standby power mode.
`In a typical television power Supply circuit, a pulse width
`modulator circuit controls the operation of the power Supply
`circuit by alternately turning the power on and off in the
`primary Side of a flyback transformer circuit. The pulse
`width modulator circuit puts the power Supply circuit into
`Standby mode turning off the power for longer periods of
`time.
`The standby cycle timer of the present invention is
`coupled to the pulse width modulator circuit. The standby
`cycle timer alternately sends “on” and “off” signals to said
`pulse width modulator circuit. When the standby cycle timer
`Sends an “on” Signal, the pulse width modulator circuit
`causes the power Supply circuit to operate in a Standby
`mode. When the standby cycle timer sends an “off” signal,
`the pulse width modulator circuit causes the power Supply
`circuit to operate in a shutdown mode. The Standby cycle
`timer causes the “on” and “off” signals to be sent to the pulse
`width modulator circuit at specific time intervals. The time
`intervals are predetermined by the choice of particular
`values for certain circuit elements in the Standby cycle timer.
`The Standby cycle timer automatically alternates between
`Sending the required “on” and "off Signals to the pulse
`width modulator circuit. The alternate “on” and “off” signals
`control the pulse width modulator So that it causes the power
`Supply circuit to automatically alternate between the Standby
`mode and the shutdown mode. When the television receives
`an external Signal to resume normal operation, the Standby
`cycle timer automatically ceases Sending the alternate “on”
`and "off Signals, and Sends only an “on” Signal to the pulse
`width modulator circuit So that the power Supply circuit can
`provide continuous operating power to the television.
`When the television receives an external Signal to cease
`normal operation, the Standby cycle timer automatically
`resumes Sending the alternate “on” and “off” Signals to the
`pulse width modulator circuit to resume alternating between
`the standby mode and the shutdown mode.
`
`VIZIO, Inc. Exhibit 1009
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 6 of 11
`
`

`

`3
`The foregoing has outlined rather broadly the features and
`technical advantages of the present invention So that those
`skilled in the art may better understand the Detailed Descrip
`tion of the invention that follows. Additional features and
`advantages of the invention will be described hereinafter
`that form the subject of the claims of the invention. Those
`skilled in the art should appreciate that they may readily use
`the conception and the Specific embodiment disclosed as a
`basis for modifying or designing other Structures for carry
`ing out the Same purposes of the present invention. Those
`skilled in the art should also realize that Such equivalent
`constructions do not depart from the Spirit and Scope of the
`invention in its broadest form.
`Before undertaking the Detailed Description, it may be
`advantageous to Set forth definitions of certain words and
`phrases used throughout this patent document: the terms
`“include” and “comprise” and derivatives thereof, mean
`inclusion without limitation; the term “or,” is inclusive,
`meaning and/or; the phrases "asSociated with and "asSoci
`ated there with,” as well as derivatives thereof, may mean to
`include, be included within, interconnect with, contain, be
`contained within, connect to or with, couple to or with, be
`communicable with, cooperate with, interleave, juxtapose,
`be proximate to, be bound to or with, have, have a property
`of, or the like; and the term “controller,” “processor,” or
`“apparatus' means any device, System or part thereof that
`controls at least one operation, Such a device may be
`implemented in hardware, firmware or Software, or Some
`combination of at least two of the same. It should be noted
`that the functionality, associated with any particular control
`ler may be centralized or distributed, whether locally or
`remotely. Definitions for certain words and phrases are
`provided throughout this patent document, those of ordinary
`skill in the art should understand that in many, if not most
`instances, Such definitions apply to prior, as well as future
`uses of Such defined words and phrases.
`BRIEF DESCRIPTION OF THE DRAWINGS
`For a more complete understanding of the present
`invention, and the advantages thereof, reference is now
`made to the following descriptions taken in conjunction with
`the accompanying drawings, wherein like numbers desig
`nate like objects, and in which:
`FIG. 1 is a simplified circuit diagram of a typical power
`Supply circuit with multiple outputs for powering a televi
`Sion Set showing the connection of the Standby cycle timer
`of the present invention within Said power Supply circuit;
`FIG. 2 is a circuit diagram of a Standby cycle timer of the
`present invention; and
`FIG. 3 is a timing diagram of the electronic Signals that
`are utilized in the present invention; and
`FIG. 4 is a flow diagram illustrating the logic of the
`operation of the alternating Standby mode apparatus of the
`present invention.
`DETAILED DESCRIPTION
`FIGS. 1 through 4, discussed below, and the various
`embodiments used to describe the principles of the present
`invention in this patent document are by way of illustration
`only and should not be construed in any way to limit the
`scope of the invention. Those skilled in the art will under
`Stand that the principles of the present invention may be
`implemented in any Suitably arranged electronic device
`capable of operating in a Standby or low power mode.
`FIG. 1 shows a simplified circuit diagram of a typical
`power supply circuit 100 for powering a television set
`
`15
`
`25
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`US 6,462.437 B1
`
`4
`comprising a flyback transformer circuit with multiple out
`puts. The primary side of the transformer of the power
`supply circuit 100 comprises a power source 102 coupled to
`an electromagnetic interference (EMI) filter 104 coupled to
`a bridge rectifier circuit 106 coupled to the primary coil 108
`of the transformer. The power supply circuit 100 is con
`trolled by a standby controller 110. In the preferred embodi
`ment of the invention the standby controller 110 is a pulse
`width modulator (PWM) control integrated circuit (IC) 110.
`For convenience, the pulse width modulator control inte
`grated circuit 110 will be referred to as the PWM circuit 110.
`PWM circuit 110 controls the operation of power supply
`circuit 100 through transistor 112.
`A feedback Signal is fed back from one of the Secondary
`side outputs through feedback loop 120 and is used to
`provide closed loop regulation of the PWM circuit 110. The
`feedback signal at the primary Side is isolated from the
`Secondary Side by an isolator circuit 130 that may employ,
`for example, an opto-isolator device of a type well known in
`the prior art.
`The Secondary Side consists of multiple outputs that are
`used to generate the different Voltage levels required in a
`typical television. For example, the television may have a
`Voltage output level connected to the high Voltage gain
`(HVG) circuit 140 that has a value of several hundred volts.
`The HVG circuit 140 signal is fed to a voltage multiplier that
`ultimately delivers the several kilovolts needed by the
`cathode ray tube (CRT) (not shown). This signal may be
`tightly regulated by feedback loop 120.
`A Second output Voltage having a value in the range of
`approximately one hundred volts to two hundred volts
`(100V 200V) is used to operate the video amplifiers 150 that
`modulate the CRT. A third output supply of approximately
`six volts (6V) is used to operate the heater 160 to heat the
`filament in the CRT. A fourth output voltage of twelve volts
`(12V) is used to drive the audio amplifiers 170. The fifth
`output voltage provides five volts (5V) for the logic circuits
`180.
`The output voltage for the video amplifiers 150 is regu
`lated by providing a linear regulator (LR) 200 at the trans
`former output. The output voltage for the audio amplifiers
`170 is regulated by a linear regulator (LR) 210 at the output.
`The output voltage for the logic circuits 180 is regulated by
`providing linear regulator (LR) 220 at the output. Only the
`output voltage for the HVG circuit 140 is well regulated by
`the primary side PWM circuit 110 through feedback loop
`120. The other output voltages would usually suffer from
`poorer performance if they were not regulated with the
`linear regulators 200, 210, and 220.
`In addition to delivering power during normal operation,
`the power Supply circuit for the television must be capable
`of going into a Standby mode. The Standby mode dissipates
`as little power as possible but still provides Some minimum
`functions. In the standby mode it is desirable to keep the
`CRT heaters 160 warm so that the television picture comes
`on nearly instantly when the television is turned back on.
`Also the power to the logic circuits 180 must be maintained
`in standby mode so that television's logic circuits 180 and
`the television's main microprocessor (not shown) can
`quickly power up when the television is turned back on.
`The power to the logic circuits 180 in standby mode is
`also used to operate the infrared (IR) remote receiver 230 via
`power Supply line 240. The IR receiver 230 receives a signal
`from the infrared (IR) detector 250 in response to a trans
`mitted infrared on/off signal from an infrared transmitter 260
`located in a typical hand-held television remote control unit.
`
`VIZIO, Inc. Exhibit 1009
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 7 of 11
`
`

`

`S
`The IR receiver 230 also contains a memory circuit 232 for
`storing signal values during the times when IR receiver 230
`is without power during the shutdown mode.
`The output voltage circuit that supplies power to the HVG
`circuit 140 has a Switch 270 in series with the load so that
`during standby mode the Switch 270 is opened to turn off
`power to the HVG circuit 140. Similarly, the output voltage
`circuit that supplies power to the video amplifiers 150 has a
`Switch 280 in series with the load so that during standby
`mode the Switch 280 is opened to turn off power to the video
`amplifiers 150. Similarly, the output voltage circuit that
`supplies power to the audio amplifiers 170 has a Switch 290
`in Series with the load So that during Standby mode the
`Switch 290 is opened to turn off power to the audio ampli
`fiers 170.
`When the standby mode is operating, switch 270, Switch
`280, and switch 290 are opened by the IR receiver 230 to
`turn off power to the respective circuit branches controlled
`by these switches. Alternatively, Switch 270, Switch 280, and
`Switch 290 may be opened by the televisions main micro
`processor (not shown) during Standby mode. As a result of
`Switch 270, Switch 280, and Switch 290 being opened during
`Standby mode, the power that is consumed by the television
`is Substantially lower in Standby mode than it is in normal
`operating mode.
`Even So, there are significant inefficiencies involved in
`operating the television power Supply circuit in a Standby
`mode. Most power Supplies run most efficiently at high
`output power levels. Power Supply operating efficiency
`drops off Significantly when the power Supply is operated at
`low output power levels. This inefficiency contributes to
`additional unnecessary power consumption. Therefore, it is
`desirable to reduce the level of power consumption in the
`Standby mode as much as possible.
`To further reduce the level of power consumption during
`Standby mode, the present invention provides an apparatus
`and method for operating the power Supply circuit with an
`alternating Standby mode. That is, the present invention
`causes the power Supply circuit to alternate between a
`Standby mode of operation and a shutdown mode.
`In the shutdown mode all power to the secondary side of
`the power Supply is turned off completely. This means that
`during the time interval of the shutdown mode the heater
`circuit 160 is turned off, and the logic circuits 180 are turned
`off, and the IR receiver 230 is turned off. If the duty ratio
`between the standby mode and the shutdown mode is
`designed to be fifty percent, then the Standby mode is on half
`of the time and the shutdown mode is on half of the time.
`Then the Standby power consumed using the alternating
`mode method of the present invention is half of the standby
`power consumed when one uses the Standard Standby mode
`method. Because the heater current in heater 160 will also be
`reduced by half, the time to start up the television will be
`Slightly increased compared to the time to Start up the
`television using the Standard Standby mode method.
`If the duty ratio between the standby mode and the
`shutdown mode is designed to be less than fifty percent, then
`the standby mode is on less than half of the time and the
`shutdown mode is on more than half of the time. Then the
`Standby power consumed using the alternating mode method
`of the present invention is less than half of the standby
`power consumed when one uses the Standard Standby mode
`method.
`To implement the alternating Standby mode of the present
`invention, a new control circuit is added to the primary Side
`of the power Supply circuit. The new control circuit is the
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`US 6,462.437 B1
`
`15
`
`25
`
`6
`standby cycle timer 300. The standby cycle timer 300
`controls the PMW circuit 110 through the PMW circuit's
`“on/off input as shown in FIG. 1. The standby cycle timer
`300 is controlled by the ON/STANDBY signal from the IR
`receiver 230 on the secondary side of the power supply
`circuit. IR receiver 230 sends either an ON signal or a
`STANDBY signal to the standby cycle timer 300. The signal
`at the standby cycle timer 300 is isolated from the secondary
`side of the power supply circuit by an isolator circuit 320
`that may employ, for example, an opto-isolator device of a
`type well known in the prior art.
`When the ON/STANDBY signal is not active (when
`normal operation of the television is in progress), the
`standby cycle timer 300 generates a continuous “on” signal
`to the PWM circuit 110. When the ON/STANDBY signal is
`activated, then the standby cycle timer 300 generates an
`alternating Signal with a preset duty ratio and frequency to
`alternately turn the PWM circuit 110 on and off.
`A preferred embodiment of the standby cycle timer 300 of
`the present invention is shown in FIG. 2. When the
`ON/STANDBY signal is high (the ON state) then the output
`of inverter 400 is low and the output of AND gate 402 is also
`low. The low output state from AND gate 402 turns off
`transistor Q1 404. When transistor Q1 404 is off, capacitor
`C 406 begins to charge from the V.
`voltage 408. The
`Voltage on capacitor C 406 begins to rise toward the Voltage
`level of the V
`voltage 408.
`Supply
`As the voltage on capacitor C 406 increases toward the
`value of the V.
`Voltage 408, the output of Comparator
`COMP 2 (410) is forced to go high as well because its
`threshold on its negative input is only one third (/) of the
`V.
`voltage 408. This is due to the fact that the value of
`resistor 412 is chosen to be twice the value of resistor 414
`and the negative input of Comparator Two 410 is connected
`to the circuit node that connects resistor 412 and resistor
`414. As a result the output of Comparator Two 410 is high
`and the input to the PWM circuit 110 is always “on”.
`When the ON/STANDBY signal goes low (when the
`television is in the standby mode) then the output of inverter
`400 is high and the output of AND gate 402 is also high
`because the V signal from Comparator One 416 is high. The
`high output state from AND gate 402 turns on transistor Q1
`404. Turning on transistor Q1 404 forces capacitor C406 to
`discharge and bring V quickly down to a value of Zero Volts.
`The threshold to the negative input of Comparator One
`416 is two thirds (%) the value of the V
`voltage 408.
`This is due to the fact that the value of resistor 418 is chosen
`to be twice the value of resistor 420 and the negative input
`of Comparator One 416 is connected to the circuit that
`connects resistor 418 and resistor 420. Because the threshold
`to the negative input of Comparator One 416 is two thirds
`(73) the value of the V.
`voltage 408, the output of
`Comparator One 416 will go low when V. drops to zero
`volts. At the same time, the output of Comparator Two 410
`will also go low, and thereby send an “off” signal to the
`PWM circuit 110. The PWM circuit 110 then will turn itself
`off.
`Now because the output of Comparator One 416 is low,
`the output of the AND gate 402 also goes low and turns off
`transistor Q1 404. After transistor Q1 404 is turned off, the
`voltage on capacitor C 406 will slowly increase with a time
`constant RC. The time constant R.C. is the product of the
`resistance of resistor R 422 and the capacitance of the
`capacitor C 406. When the voltage at V reaches a value of
`one third (/) of the value of the V
`voltage 408, the
`Supply
`output of Comparator Two 410 goes high. A high output
`
`VIZIO, Inc. Exhibit 1009
`VIZIO, Inc. v. Maxell, LTD, IPR2022-01459
`Page 8 of 11
`
`

`

`7
`from Comparator Two 410 sends an “on” signal to PWM
`circuit 110. The “on” signal turns on the PWM circuit 110
`and causes the power supply circuit 100 to resume the
`Standby mode.
`When the voltage at V reaches two thirds (%) of the
`V.
`voltage 408, the output of Comparator One 416 goes
`high and the cycle repeats itself as shown in FIG. 3. By
`Setting appropriate values for the capacitor C406 and for the
`resistors 412,414, 418, 420, and 422, the frequency and the
`duty ratio of the alternating Standby mode Signal may be
`easily adjusted to any desired values.
`The operation of the power Supply circuit utilizing the
`present invention that has been described above is illustrated
`in the timing diagram shown in FIG. 3. Following the
`reception of an “off” signal from the IR transmitter 260, the
`ON/STANDBY output signal from the IR receiver 230 goes
`low. At the same time the signals V, V, and PWM on/off
`all go low, and the power supply circuit 100 is put into the
`shutdown mode. The Switching signal from the PWM circuit
`110 is completely turned off. After a period of time deter
`mined by the component values of resistor R 422 and
`capacitor C 406, the standby mode is activated. Now the
`PWM circuit 110 enters its standby mode (low power mode)
`of operation which is usually a form of burst mode in which
`the PWM circuit 110 cycles between “high frequency
`Switching” and “off” at a rate of a few kilohertz.
`The alternation of the shutdown modes and the standby
`modes continues until the IR transmitter 260 sends an “on”
`signal that is received by the IR receiver 230. Since the IR
`receiver 230 is only active during the standby mode, the
`transmission must be sent Several times to ensure that it
`overlaps with the time during which the IR receiver 230 is
`on. In FIG. 3 the first “on” transmission from the IR
`transmitter 260 arrives during a shutdown period and is not
`received. The second “on” transmission from the IR trans
`mitter 260 arrives during a standby period and is received.
`IR receiver 230 stores signal information in memory 232
`so that IR receiver 230 can remain in the standby mode when
`it is powered up during alternating Standby cycles. That is,
`memory 232 stores signal information for IR receiver 230
`during the times when IR receiver 230 is without power
`during the shutdown mode.
`The duration of the standby mode and the duration of the
`shutdown mode can be on the order of one fourth (4) of a
`Second. Because the time required to push the “power on
`button in a television is likely be more than one fourth (4)
`of a second, it is likely that the television will be in at least
`a portion of one standby mode cycle when the “power on
`button is pushed and the corresponding “on code” is
`received. Therefore television viewers in most instances will
`be able to turn on the television with a single push of the
`“power on' button. If the television does not turn on after the
`first push of the “power on' button, the viewer can simply
`push the “power on' button again.
`FIG. 4 is a flow diagram illustrating the logic of the
`operation of an exemplary alternating Standby mode appa
`ratus of the present invention. In decision step 500 a
`determination is made whether the electronic device is on. If
`the electronic device is on, then the normal operating power
`is used as shown in operation step 560. If the electronic
`device is not on, then the Standby power is turned on as
`shown in operation step 510.
`Then the electronic device is operated in the shutdown
`mode for one cycle as shown in operation step 520. Then the
`electronic device is operated in the Standby mode for one
`cycle as shown in operation step 530. Then in decision step
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`US 6,462.437 B1
`
`15
`
`25
`
`8
`540 a determination is again made whether the electronic
`device is on. If the electronic device is on, then the Standby
`power is turned off as shown in operation step 550 and the
`normal operating power is used as shown in operation Step
`560.
`If the electronic device is not on, then the electronic
`device is again operated in the shutdown mode for one cycle
`as shown in operation step 520 and the cycle repeats. The
`alternation between the standby mode and the shutdown
`mode continues indefinitely until the electronic device is
`turned back on.
`Although the present invention has been described in
`detail with respect to a television power Supply, those skilled
`in the art should understand that they can make various
`changes, Substitutions and alterations herein without depart
`ing from the Spirit and Scope of the invention in its broadest
`form.
`What is claimed is:
`1. An apparatus for reducing the level of power consump
`tion in a television having television component circuitry
`that is operative in a Standby mode comprising:
`an electronic control circuit capable of alternately shutting
`off power and turning on power to Said television.
`component circuitry when Said television component
`circuitry is operating in a Standby mode,
`a transformer having a primary winding and multiple
`Secondary windings for Supplying power to the cir
`cuitry of the electronic device,
`means for coupling the transformer primary winding to
`the electronic control circuit, and
`means for Supplying a control signal to the electronic
`control circuit that is independent of transformer Volt
`age in the Standby mode of the electronic device.
`2. The apparatus as Set forth in claim 1 wherein Said
`electronic control circuit capable of alternately shutting off
`power and turning on power to Said circuitry when Said
`circuitry is operating in a Standby mode comprises: a
`Standby cycle timer circuit for controlling the Supply of
`power to Said circuitry.
`3. An apparatus as claimed in claim 1 wherein Said
`electronic device comprises a Standby controller for con
`trolling power to Said circuitry to cause Said circuitry to
`operate in a Standby mode, and wherein Said electronic
`control circuit capable of alternately shutting off power and
`turning on power to Said circuitry when Said circuitry is
`operating in a Standby mode comprises:
`an electronic control circuit for alternately shutting off
`and turning on Said Standby controller to cause power.
`to Said circuitry to alternately shut off and turn on when
`Said circuitry is operating in a Standby mode.
`4. The apparatus as Set forth in claim 3 wherein Said
`electronic control circuit capable of alternately shutting off
`and turning on Said Standby controller to cause power to Said
`circuitry to alternately shut off and turn on when Said
`circuitry is operating in a Standby mode comprises:
`a Standby cycle timer circuit for controlling Said Standby
`controller to control the Supply of power to Said cir
`cuitry.
`5. The apparatus as set forth in claim 4 wherein said
`Standby cycle timer circuit comprises:
`an electronic control circuit capable of continuous