US6232964B1
Expired / Lapsed
US
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Power control circuit for display device having PFC function
Assignee: Samsung Electronics Co Ltd
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Filing: 1998-09-02
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Granted: 2001-05-15
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Expires: 2018-09-02
Abstract
Abstract A power control circuit of a display device having a power factor correction (PFC) function includes a microcomputer to determine a display power management signaling (DPMS) mode of the display device by discriminating a sync signal input from a host computer; a rectifier to output DC power by rectifying an AC power input; a PFC controller, having a pulse width modulation (PWM) circuit, to output a PWM signal according to the DPMS mode determined by the microcomputer, the PFC controller receiving the DC power output of the rectifier; a PFC power circuit, using a DC current from the rectifier, to generate a power-factor-corrected power output based on the PWM signal output from the PFC controller; and a frequency-controlled oscillator to supply the PWM circuit of the PFC controller with a predetermined oscillation signal. The frequency-controlled oscillator includes frequency-controlling elements such as capacitors selectively activated according to the DPMS mode determined by the microcomputer; and an isolation device such as an optical coupler, connected between the microcomputer and at least one of the frequency-controlling elements, to provide electrical isolation between the activated frequency-controlling element and the microcomputer. The microcomputer includes at least one output port outputting a DPMS mode signal based on the determined DPMS mode. The microcomputer outputs a first DPMS mode signal when the determined DPMS mode is a normal mode or a standby mode and outputs a second DPMS mode signal when the determined DPMS mode is a suspend mode or a power-off mode. The power control circuit does not cut off the DC power input to the PFC control circuit and maintains proper PFC control throughout the stages of DPMS operation.
Inventors
- 👤 Joo-Hyoung Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:21
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/63; H02; H02M; H02M1/00; H02M1/42; H02M1/4208; H02M1/4225; G; G09; G09G; G09G1/00; G09G1/06; G09G1/14; G09G1/16; G09G2330/00; G09G2330/02; G09G2330/021; H02M1/0003; H02M1/0032; H02M1/0083; H02M1/009; Y; Y02; Y02B; Y02B70/00; Y02B70/10
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
147 words
A power control circuit for use in a display device having a power factor correction (PFC) function, comprising: a microcomputer to determine a display power management signaling (DPMS) mode of the display device by discriminating a sync signal input from a host computer, to generate a DPMS mode signal; a rectifier to output DC power by rectifying an AC power input; a PFC controller, having a pulse width modulation (PWM) circuit, to output a PWM signal according to the DPMS mode signal determined by said microcomputer, said PFC controller receiving the DC power output of said rectifier; a PFC power circuit, using a DC current from said rectifier, to generate a power-factor-corrected power output based on the PWM signal output from said PFC controller; and a frequency-controlled oscillator to supply the PWM circuit of said PFC controller with an oscillation signal based upon the DPMS mode signal.
Claim 2
Dependent Claim
147 words
A power control circuit for use in a display device having a power factor correction (PFC) function, comprising: a microcomputer to determine a display power management signaling (DPMS) mode of the display device by discriminating a sync signal input from a host computer, to generate a DPMS mode signal; a rectifier to output DC power by rectifying an AC power input; a PFC controller, having a pulse width modulation (PWM) circuit, to output a PWM signal according to the DPMS mode signal determined by said microcomputer, said PFC controller receiving the DC power output of said rectifier; a PFC power circuit, using a DC current from said rectifier, to generate a power-factor-corrected power output based on the PWM signal output from said PFC controller; and a frequency-controlled oscillator to supply the PWM circuit of said PFC controller with an oscillation signal based upon the DPMS mode signal.
Claim 3
Dependent Claim
29 words
The circuit as claimed in claim 1 , wherein said frequency-controlled oscillator comprises a plurality of frequency-controlling elements selectively activated according to the DPMS mode determined by said microcomputer.
Claim 4
Dependent Claim
19 words
The circuit as claimed in claim 2 , wherein said plurality of frequency-controlling elements is made up of capacitors.
Claim 5
Dependent Claim
43 words
The circuit as claimed in claim 2 , wherein said frequency-controlled oscillator further comprises an isolation device, connected between said microcomputer and at least one of said plurality of frequency-controlling elements, to provide electrical isolation between the activated frequency-controlling element and said microcomputer.
Claim 6
Dependent Claim
16 words
The circuit as claimed in claim 4 , wherein said isolation device is an optical coupler.
Claim 7
Dependent Claim
61 words
The circuit as claimed in claim 1 , wherein said microcomputer outputs a the DPMS mode signal as a first waveform when the determined DPMS mode is one of a normal mode and a standby mode and outputs the DPMS mode signal as a second waveform when the determined DPMS mode is one of a suspend mode and a power-off mode.
Claim 8
Dependent Claim
36 words
The circuit as claimed in claim 1 , wherein said microcomputer has at least two output ports to output the DPMS mode signal so as to provide at least three different frequencies of the oscillation signal.
Claim 9
Dependent Claim
46 words
The circuit as claimed in claim 2 , wherein said microcomputer has at least two output ports connected to ones of said plurality of frequency-controlling elements, respectively, to output the DPMS mode signal so as to selectively activate said ones of said plurality of frequency-controlling elements.
Claim 10
Dependent Claim
54 words
The circuit as claimed in claim 1 , wherein: said microcomputer comprises an internal analog-to-digital converter to output the DPMS mode signal as an analog signal; and said frequency controlled oscillator comprises at least one active element to output a plurality of different frequencies of the oscillation signal in accordance with the analog signal.
Claim 11
Dependent Claim
105 words
A power control circuit for use in a display device and receiving a direct current (DC), DC power and a display power management signaling (DPMS) mode signal indicative of one of a plurality of DPMS modes of the display device, the power control circuit comprising: a frequency-controlled oscillator to output an oscillation signal having a frequency based upon the DPMS mode signal; a power factor correction (PFC) controller to output a pulse width modulation (PWM) signal using said DC power, according to the oscillation signal; and a PFC power circuit, to generate a power-factor-corrected power output using the DC current, according to the PWM signal.
Claim 12
Dependent Claim
105 words
A power control circuit for use in a display device and receiving a direct current (DC), DC power and a display power management signaling (DPMS) mode signal indicative of one of a plurality of DPMS modes of the display device, the power control circuit comprising: a frequency-controlled oscillator to output an oscillation signal having a frequency based upon the DPMS mode signal; a power factor correction (PFC) controller to output a pulse width modulation (PWM) signal using said DC power, according to the oscillation signal; and a PFC power circuit, to generate a power-factor-corrected power output using the DC current, according to the PWM signal.
Claim 13
Dependent Claim
54 words
The power control circuit as claimed in claim 10 , wherein said frequency-controlled oscillator comprises: an oscillator to output the oscillation signal; and a plurality of passive elements, connected to the oscillator, at least one of which is selectively enabled according to the DPMS mode signal, to vary the frequency of the oscillation signal.
Claim 14
Dependent Claim
79 words
The power control circuit as claimed in claim 11 , further comprising: a processing circuit to determine the one DPMS mode and output the DPMS mode signal according to a horizontal sync signal and a vertical sync signal received from an external source; wherein said frequency-controlled oscillator further comprises an isolation circuit connected between the processing circuit and the at least one passive element, to prevent stray capacitance between the processing circuit and the at least one passive element.
Claim 15
Dependent Claim
44 words
The power control circuit as claimed in claim 10 , wherein said frequency-controlled oscillator comprises: an oscillator to output the oscillation signal; and an active element connected to the oscillator, to vary the frequency of the oscillation signal according to the DPMS mode signal.
Claim 16
Dependent Claim
92 words
The power control circuit as claimed in claim 13 , further comprising: a processing circuit to determine the one DPMS mode and output the DPMS mode signal according to a horizontal sync signal and a vertical sync signal received from an external source, the processing circuit having an internal digital-to-analog converter to output the DPMS mode signal as an analog signal; wherein the active element is a varacter diode connected to the oscillator, to vary the frequency and a duty ratio of the oscillation signal according to the analog DPMS mode signal.
Claim 17
Dependent Claim
215 words
A power control circuit for use in a display device and receiving a direct current (DC), DC power and a display power management signaling (DPMS) mode signal indicative of one of a plurality of DPMS modes of the display device, the power control circuit comprising: a control circuit to generate a control signal based upon the DPMS mode signal; a power factor correction (PFC) controller to output a pulse width modulation (PWM) signal using said DC power, according to the control signal, in a number of the plurality of DPMS modes; a PFC power circuit, to generate a power-factor-corrected power output using the DC current, according to the PWM signal, in each of the number of the plurality of DPMS modes; and a rectifier to generate the DC power and DC current and connected directly to the PFC controller and PFC power circuit; wherein the control circuit comprises a microcomputer to determine the one DPMS mode and output the DPMS mode signal according to a horizontal sync signal and a vertical sync signal received from an external source, and a frequency-controlled oscillator to output the control signal as an oscillation signal having a frequency based upon the DPMS mode signal, the oscillation signal varying a frequency of the PWM signal output from the PFC controller.
Claim 18
Dependent Claim
215 words
A power control circuit for use in a display device and receiving a direct current (DC), DC power and a display power management signaling (DPMS) mode signal indicative of one of a plurality of DPMS modes of the display device, the power control circuit comprising: a control circuit to generate a control signal based upon the DPMS mode signal; a power factor correction (PFC) controller to output a pulse width modulation (PWM) signal using said DC power, according to the control signal, in a number of the plurality of DPMS modes; a PFC power circuit, to generate a power-factor-corrected power output using the DC current, according to the PWM signal, in each of the number of the plurality of DPMS modes; and a rectifier to generate the DC power and DC current and connected directly to the PFC controller and PFC power circuit; wherein the control circuit comprises a microcomputer to determine the one DPMS mode and output the DPMS mode signal according to a horizontal sync signal and a vertical sync signal received from an external source, and a frequency-controlled oscillator to output the control signal as an oscillation signal having a frequency based upon the DPMS mode signal, the oscillation signal varying a frequency of the PWM signal output from the PFC controller.
Claim 19
Dependent Claim
175 words
A power control circuit for use in a display device, comprising: a processing circuit to determine a display power management signaling (DPMS) mode of the display device by discriminating a sync signal input from an external source, to generate a DPMS mode signal; a rectifier to output DC power and a DC current by rectifying an AC power input; a control circuit to generate a control signal based upon the DPMS mode signal; a power factor correction (PFC) controller connected to said rectifier, to receive the control signal in a plurality of DPMS modes, to output a pulse width modulation (PWM) signal using said DC power according to the control signal; and a PFC power circuit connected to said rectifier, to generate a power-factor-corrected power output using the DC current according to the PWM signal, in the plurality of DPMS modes, wherein said control circuit comprises a frequency-controlled oscillator to output the control signal as an oscillation signal having a frequency based upon the DPMS mode signal, to adjust a frequency of the PWM signal.
Claim 20
Dependent Claim
175 words
A power control circuit for use in a display device, comprising: a processing circuit to determine a display power management signaling (DPMS) mode of the display device by discriminating a sync signal input from an external source, to generate a DPMS mode signal; a rectifier to output DC power and a DC current by rectifying an AC power input; a control circuit to generate a control signal based upon the DPMS mode signal; a power factor correction (PFC) controller connected to said rectifier, to receive the control signal in a plurality of DPMS modes, to output a pulse width modulation (PWM) signal using said DC power according to the control signal; and a PFC power circuit connected to said rectifier, to generate a power-factor-corrected power output using the DC current according to the PWM signal, in the plurality of DPMS modes, wherein said control circuit comprises a frequency-controlled oscillator to output the control signal as an oscillation signal having a frequency based upon the DPMS mode signal, to adjust a frequency of the PWM signal.
Claim 21
Dependent Claim
121 words
A power control circuit for use in a display device and receiving a direct current (DC), DC power and a display power management signaling (DPMS) mode signal indicative of one of a plurality of DPMS modes of the display device, the power control circuit comprising: a frequency-controlled oscillator to output an oscillation signal having a frequency based upon the DPMS mode signal; a power factor correction (PFC) controller to output a pulse width modulation (PWM) signal using said DC power, according to the oscillation signal, even when the DPMS mode signal is indicative of a power-savings mode of the display device; and a PFC power circuit, to generate a power-factor-corrected power output using the DC current, according to the PWM signal.
Claim 22
Dependent Claim
121 words
A power control circuit for use in a display device and receiving a direct current (DC), DC power and a display power management signaling (DPMS) mode signal indicative of one of a plurality of DPMS modes of the display device, the power control circuit comprising: a frequency-controlled oscillator to output an oscillation signal having a frequency based upon the DPMS mode signal; a power factor correction (PFC) controller to output a pulse width modulation (PWM) signal using said DC power, according to the oscillation signal, even when the DPMS mode signal is indicative of a power-savings mode of the display device; and a PFC power circuit, to generate a power-factor-corrected power output using the DC current, according to the PWM signal.
Claim 23
Dependent Claim
37 words
The power control signal as claimed in claim 17 , wherein said PFC controller outputs the PWM signal even when the DPMS mode signal is indicative of a standby state, a suspend state or a power-off mode.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-05-14 | 2004-11-13 | 2005-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-05-14 | 2008-11-13 | 2009-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-05-14 | 2012-11-13 | 2013-05-15 | $7700.00 | Window Closed / Lapsed |