GB2327025A - Scan-frequency-dependent drive signal amplitude in a horizontal deflection circuit for a multi-mode monitor - Google Patents
Scan-frequency-dependent drive signal amplitude in a horizontal deflection circuit for a multi-mode monitor Download PDFInfo
- Publication number
- GB2327025A GB2327025A GB9809955A GB9809955A GB2327025A GB 2327025 A GB2327025 A GB 2327025A GB 9809955 A GB9809955 A GB 9809955A GB 9809955 A GB9809955 A GB 9809955A GB 2327025 A GB2327025 A GB 2327025A
- Authority
- GB
- United Kingdom
- Prior art keywords
- signal
- horizontal
- transistor
- accordance
- resistor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 230000001419 dependent effect Effects 0.000 title 1
- 239000003990 capacitor Substances 0.000 description 8
- 238000010276 construction Methods 0.000 description 5
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 4
- 230000003247 decreasing effect Effects 0.000 description 3
- 238000007599 discharging Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N3/00—Scanning details of television systems; Combination thereof with generation of supply voltages
- H04N3/10—Scanning details of television systems; Combination thereof with generation of supply voltages by means not exclusively optical-mechanical
- H04N3/16—Scanning details of television systems; Combination thereof with generation of supply voltages by means not exclusively optical-mechanical by deflecting electron beam in cathode-ray tube, e.g. scanning corrections
- H04N3/22—Circuits for controlling dimensions, shape or centering of picture on screen
- H04N3/23—Distortion correction, e.g. for pincushion distortion correction, S-correction
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N3/00—Scanning details of television systems; Combination thereof with generation of supply voltages
- H04N3/10—Scanning details of television systems; Combination thereof with generation of supply voltages by means not exclusively optical-mechanical
- H04N3/16—Scanning details of television systems; Combination thereof with generation of supply voltages by means not exclusively optical-mechanical by deflecting electron beam in cathode-ray tube, e.g. scanning corrections
- H04N3/27—Circuits special to multi-standard receivers
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K4/00—Generating pulses having essentially a finite slope or stepped portions
- H03K4/06—Generating pulses having essentially a finite slope or stepped portions having triangular shape
- H03K4/08—Generating pulses having essentially a finite slope or stepped portions having triangular shape having sawtooth shape
- H03K4/48—Generating pulses having essentially a finite slope or stepped portions having triangular shape having sawtooth shape using as active elements semiconductor devices
- H03K4/60—Generating pulses having essentially a finite slope or stepped portions having triangular shape having sawtooth shape using as active elements semiconductor devices in which a sawtooth current is produced through an inductor
- H03K4/62—Generating pulses having essentially a finite slope or stepped portions having triangular shape having sawtooth shape using as active elements semiconductor devices in which a sawtooth current is produced through an inductor using a semiconductor device operating as a switching device
- H03K4/64—Generating pulses having essentially a finite slope or stepped portions having triangular shape having sawtooth shape using as active elements semiconductor devices in which a sawtooth current is produced through an inductor using a semiconductor device operating as a switching device combined with means for generating the driving pulses
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N3/00—Scanning details of television systems; Combination thereof with generation of supply voltages
- H04N3/10—Scanning details of television systems; Combination thereof with generation of supply voltages by means not exclusively optical-mechanical
- H04N3/16—Scanning details of television systems; Combination thereof with generation of supply voltages by means not exclusively optical-mechanical by deflecting electron beam in cathode-ray tube, e.g. scanning corrections
- H04N3/22—Circuits for controlling dimensions, shape or centering of picture on screen
- H04N3/223—Controlling dimensions
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G1/00—Control arrangements or circuits, of interest only in connection with cathode-ray tube indicators; General aspects or details, e.g. selection emphasis on particular characters, dashed line or dotted line generation; Preprocessing of data
- G09G1/04—Deflection circuits ; Constructional details not otherwise provided for
Abstract
A horizontal deflection circuit for a multi-mode monitor includes an oscillating section 100 for receiving an externally-supplied horizontal sync signal and for generating an oscillating signal. A horizontal driving section 200 is provided for amplifying the oscillating signal in accordance with an amplitude of the externally-supplied voltage source Vcc and for generating a driving signal. A microprocessor 300 is arranged to determine the mode in accordance with the frequency of the externally-supplied horizontal sync signal and for outputting a control signal CS to control the amplitude of the driving signal in accordance with the determined mode. A driving signal controlling section 400 is connected to an output terminal of the microprocessor 300 for determining the amplitude of the driving signal in accordance with the control signal. A horizontal output section 500 is arranged to be switched on and off to generate a horizontal deflection signal of sawtooth waveform, and to supply the generated horizontal deflection signal to a horizontal deflection coil HDY.
Description
HORIZONTAL DEFLECTION CIRCUIT FOR A MULTIMOIXE MONITOR
The present invention relates to a horizontal deflection circuit for a multimode monitor for driving a horizontal deflection coil.
Description of the Prior Art
A conventional monitor is an apparatus which displays a video signal in accordance with an externally-supplied synchronization(sync) signal. In the above conventional monitor, a mode of the monitor is determined in accordance with the mode of the video card, a classification of the mode of monitor is as follows.
stable 11
video mode horizontal vertical resolution frequency (KHz) frequency(Hz) (Horizontal*Verticat) CGA 15.75 60 640*200 EGA 21.8 60 640*200 VGA 31.5 60170 720*3501640*480 SVGA 35-37 interlace 1024*768 HIGH 64-75 60-70 1024*768 RESOLUTION MODE 1280*1024 As shown in table 1, a frequency of the horizontal sync signal and a frequency of the vertical sync signal are different in accordance with the mode of the video card and the rating range of frequency of a horizontal sync signal is about 30-70KHz.
When the mode of multi-mode monitor is changed, the monitor is readjusted in accordance with the changed mode. The readjusting factors are a size and a position of image, a synchronization of horizontal and vertical sync signal, an optimization of deflection, and an amplitude of deflection correcting signal.
In the conventional multi-mode monitor, an electron emitted from a cathode of a Cathode Ray Tube(CRT) is accelerated in accordance with a voltage applied to a grid terminal and then is deflected by a magnetic field generated at a deflection coil. The deflected electron collides with a phosphor screen and the point of collision of the phosphor screen is moved.
The deflecting distance is proportional to the intensity of the magnetic field and the intensity of the magnetic field is proportional to the quantity of current of sawtooth waveform which flows in the deflection coil. Therefore, the multi-mode monitor is equipped with a horizontal deflection coil for deflecting the electron in the horizontal direction from left to right at a constant speed and returning it from right to left at a high speed and a vertical deflection coil for deflecting it in the vertical direction.
Figure 1 is a view for showing a current of sawtooth waveform supplied to a horizontal deflection coil in a conventional multi-mode monitor. Here, the electron is deflected to the leftmost end point of the phosphor screen at a point a. Since the current does not flow to the horizontal deflection coil, the electron advances straight to a point b. Further, since the quantity of current gradually increases, the electron is deflected to the rightmost end point of the phosphor screen at a point c. Thereafter, the quantity of current is suddenly reduced and the electron is again deflected to the leftmost end point at a point a 1.
Figure 2 is a view for showing a construction of a conventional horizontal deflection circuit for a multi-mode monitor. Here, the conventional horizontal deflection circuit comprises an oscillator 10 for oscillating and pulse-width modulating an externally-supplied horizontal sync signal in accordance with the frequency thereof and outputting a oscillating signal, a horizontal driving section 12 for amplifying the oscillating signal in accordance with a voltage of an externally-supplied voltage source Vcc and for generating a driving signal, and a horizontal output section 14 for generating a horizontal deflecting signal of sawtooth waveform in accordance with the horizontal driving signal and for supplying the horizontal deflecting signal to a horizontal deflection coil HDY.
The horizontal driving section 12 comprises resistors 21 and 22 connected in series between an output terminal of the oscillator 10 and the ground for dividing the oscillating signal, a transistor 23 for switching in accordance with the dividing signal of the resistors 21 and 22, a resistor 26 and a horizontal driving transformer 27 connected in parallel between an input side of the extemally-supplied voltage source and a collector side of the transistor 23 for supplying the externally-supplied voltage source Vcc (about 24V) to a first coil of the horizontal driving transformer 207 in accordance with a switching state of the transistor 23 and for generating a driving signal, a resistor 28 for determining an amplitude of driving signal, a resistor 30 and a capacitor 31 for charging an output signal of the resistor 26 when the transistor 23 is switched off.
The horizontal output section 14 includes a horizontal output transistor 41 for switching in accordance with the driving signal, a capacitor 42 connected between a collector side of the transistor 41 and grounded for charging a energy which is charged by the horizontal deflecting coil HDY when the transistor 41 is switched off and for discharging the charged energy to the horizontal deflection coil HDY, a diode 43 for switching in accordance with the amplitude of energy which is charged by the horizontal deflection coil HDY and for reducing the quantity of current which flows to the horizontal deflection coil HDY.
In the above described construction of the conventional horizontal deflection circuit for a multi-mode monitor, and the frequency of horizontal sync signal Hs is supplied to the oscillator 10, and the oscillator 10 converts a horizontal sync signal Hs to the oscillating signal. The oscillating signal is supplied to the resistors 21 and 22, and the resistors 21 and 22 divide the oscillating signal and output a dividing signal.
The dividing signal is supplied to the transistor 23 and the transistor 23 switches on and off in accordance with the dividing signal. When the transistor 23 is switched on, the externally-supplied voltage source Vcc is supplied to horizontal driving transformer 27 through the resistor 26. Therefore, a current flows in the first coil of the horizontal driving transformer 26 , so the second coil of the horizontal driving transformer 27 is excited.
That is, the oscillating signal is amplified in accordance with an operation of the horizontal driving transformer 27, and the horizontal driving transformer 27 outputs the driving signal.
The driving signal is supplied to the resistor 28, and the amplitude of the driving signal is determined by a resistance of resistor 28. The driving signal of the resistor 28 is supplied to the horizontal output transistor 41 of the horizontal output section 14.
In the meantime, when the transistor 23 is switched off in accordance with the dividing signal, the externally-supplied voltage source Vcc is supplied to the capacitor 31 through the resistors 26 and 30, and the capacitor 31 charges the externally-supplied voltage source Vcc.
The horizontal output transistor 41 switches on and off in accordance with the driving signal. In other words, when the horizontal output transistor 41 is switched on in accordance with the driving signal, a current flows in the horizontal deflection coil HDY to generate the magnetic field. The electron is deflected in accordance with the intensity of the magnetic field generated by the horizontal deflection coil HDY (see Figure 1, between points b and c).
When the horizontal output transistor 41 is switched off in accordance with the driving signal, the energy in horizontal deflection coil HDY is charged to the capacitor 42. The charged energy of capacitor 42 is discharged to the horizontal deflection coil HDY, so the horizontal deflection coil HDY is charged with the energy (see Figure 1, between point c and point a1). The diode 43 switches on and off according to the quantity of energy which is charged in the horizontal deflection coil HDY. When the diode 43 is switched on, the quantity of current which flows to the horizontal deflection coil HDY is zero (see Figure 1, between point a and b).
However, in conventional horizontal deflection circuit for a multi-mode monitor, the amplitude of driving signal when the frequency of horizontal sync signal is higher than a reference frequency (about 45KHz) is equal to that of driving signal when the frequency of horizontal sync signal is lower than the reference frequency, so the quantity of current of sawtooth waveform which is supplied to the horizontal deflection coil is the same. Accordingly, the quality of picture deteriorates.
SUMMARY OF THE INVENTION
It is an object of the present invention to reduce the problems of known horizontal deflection circuits.
According to a first aspect of the present invention there is provided a horizontal deflection circuit for a video signal processing system comprising means for generating a driving signal, means for controlling the amplitude of the driving signal in accordance with the frequency of an extemally supplied horizontal sync signal, and generating means for generating a horizontal deflection signal having a sawtooth waveform, wherein said generating means is controlled by said adjusted driving signal whereby the horizontal deflection signal is stabilised.
The invention also extends to a horizontal deflection circuit for a multimode monitor including an oscillating section for receiving a frequency of horizontal sync signal and outputting an oscillating signal. A horizontal driving section amplifies the oscillating signal in accordance with an amplitude of externally-supplied voltage source and generates a driving signal, a horizontal output section generates a horizontal deflection signal of sawtooth waveform and supplies the horizontal deflection signal to a horizontal deflection coil.
Additionally, a microprocessor determines a mode of monitor in accordance with the frequency of the horizontal sync signal and generates a control signal for adjusting an amplitude of the driving signal and a driving signal control section connected between the output tenninals of the horizontal driving section and the horizontal output section adjusts the amplitude of driving signal.
In an embodiment of the invention, the oscillating signal supplied from the oscillating section is supplied to the horizontal driving section which amplifies the oscillating signal and outputs the driving signal. The driving signal is supplied to the horizontal output section which switches on and off in accordance with the driving signal and which generates the horizontal deflection signal of sawtooth waveform. The horizontal deflection signal is supplied to the horizontal deflection coil. When the frequency of horizontal sync signal is higher than a reference frequency, the microprocessor generates the control signal of a high level, and the control signal of the high level is supplied to the driving signal control section which increases the amplitude of driving signal. Consequently, the quantity of the current of the horizontal deflection signal and a horizontal picture size increases, so the quality of a picture can be enhanced.
DESCRIPTION OF EMBODIMENTS OF THE INVENTION
Embodiments of the present invention will hereinafter be described, by way of example, with reference to the accompanying drawings, in which:
Figure 1 is a view showing a current of sawtooth waveform supplied to a horizontal deflection coil in a conventional multi-mode monitor;
Figure 2 is a view showing the construction of a conventional horizontal deflection circuit for a multi-mode monitor; and
Figure 3 is a view showing the construction of a horizontal deflection circuit for a multi-mode monitor of an embodiment of the present invention.
A horizontal deflection circuit for a multi-mode monitor of an embodiment of the invention is shown in Figure 3 in which reference numeral 100 denotes an oscillating section for receiving an externally-supplied horizontal sync signal and for generating an oscillating signal. Reference numeral 200 denotes a horizontal driving section for amplifying the oscillating signal in accordance with a voltage of an externally-supplied voltage source Vcc and for outputting a driving signal.
Reference numeral 300 denotes a microprocessor for determining a mode in accordance with a frequency of the horizontal sync signal and for generating a control signal CS for controlling an amplitude of the driving signal.
Reference numeral 400 denotes a driving signal control section connected to an output terminal of the horizontal driving section 200 for determining the amplitude of driving signal in accordance with the control signal of the microprocessor 300.
Reference numeral 500 denotes a horizontal output section for switching on and off, generating a horizontal deflection signal of sawtooth waveform, and for supplying the horizontal deflection signal to a horizontal deflection coil HDY.
Here, the horizontal driving section 200 comprises, as shown in Figure 2, the resistors 201-202, 206, and 208, the capacitor 203, and the horizontal driving transformer 207. And the horizontal output section 500 includes, as shown in
Figure 2, the horizontal output transistor 501, the capacitor 502, and the diode 503.
In the meantime, the construction of the driving signal controlling section 400 will be described in more detail.
An output terminal of the microprocessor 300 is serially connected to resistors 402 and 403 for dividing the control signal CS, and the output terminal of the resistors 201 and 202 is connected to a base side of a transistor 404 for switching in accordance with the dividing signal. The output terminal of the resistor 403 is grounded.
A collector side of the transistor 404 is connected to a base side of a transistor 405 for switching on and off in accordance with a switching state of the transistor 404.
A collector side of the transistor 404 is connected to a resistor 406 for passing a current when the transistor 404 is switched on, and the output terminal of resistor 406 is connected to a base side of transistor 405. A resistor 407 is connected between the base of transistor and an emitter side thereof to pass a current which flows from the second coil of the horizontal driving transformer 207 to the transistor 404 when the transistor 405 is switched off. An emitter side of the transistor 404 is grounded.
The emitter side of the transistor 405 is connected to the input terminal of horizontal driving transformer 207, and a side collector side of the transistor 405 is connected to a resistor 408 for determining the amplitude of driving signal, and the output terminal of resistor 408 is connected to the output terminal of resistor 208. In this embodiment, the transistor 404 is of an NPN-type and the transistor 405 is of a PNP-type.
In connection with this embodiment of the present invention constructed as above, operations and effect of the horizontal deflection circuit for the multimode monitor will be described with reference to the accompanying drawing.
The horizontal sync signal Hs is supplied to the horizontal oscillating section 100, the horizontal oscillating section 100 receives the horizontal sync signal Hs and outputs the oscillating signal, and the oscillating signal is supplied to the horizontal driving section 200.
The driving section 200 amplifies the oscillating signal and generates the driving signal. In the embodiment, the process which amplifies the oscillating signal and generates the driving signal has been as described above, therefore, the detail description thereof is omitted.
In the meantime, the horizontal sync signal Hs is supplied to the microprocessor 300, and the microprocessor 300 determines the mode corresponding to the horizontal sync signal Hs. That is, when the frequency of horizontal sync signal Hs is lower than about 45KHz, the microprocessor 300 outputs the control signal CS of a low level, and the control signal CS of the low level is supplied to the driving signal controlling section 400.
The control signal CS of the low-level is supplied to the resistors 402 and 403, and the resistors 402 and 403 divide the control signal CS and output a dividing signal.
The dividing signal is supplied to the transistor 404, so the transistor 404 switches off. The driving signal of horizontal driving transformer 207 is supplied to the base side of transistor 405 through the resistor 407, so the transistor 405 switches off.
Therefore, the amplitude of driving signal is determined by a resistance of resistor 208.
That is, the amplitude of driving signal is increased and the increased driving signal is supplied to the horizontal output transistor 501 of horizontal output section 500. Therefore, the quantity of current of sawtooth waveform which flows to horizontal deflection coil HDY increases in accordance with the increased driving signal, so the horizontal size increases.
On the other hand, when the frequency of horizontal sync signal Hs is higher than about 45KHz, the microprocessor 300 outputs the control signal CS of the high level, and the control signal CS of the high level is supplied to the driving signal controlling section 400.
The control signal CS of high level is supplied to the resistors 402 and 403, the resistors 402 and 403 divide the control signal CS and output a dividing signal.
The dividing signal is supplied to the transistor 404, so the transistor 404 switches on. Therefore the driving signal of horizontal driving transformer 207 is supplied to the ground through the resistors 406 and 407, and the collector and emitter side of transistor 404. Further, the output signal of resistor 207 is supplied to the base side of transistor 405, so transistor 405 switches on.
Therefore, the amplitude of driving signal is determined by a resistance of resistors 208 and 408.
In other words, the amplitude of driving signal is decreased and the decreased driving signal is supplied to the horizontal output transistor 501 of horizontal output section 500. Therefore, the quantity of current of sawtooth waveform which flows to horizontal deflection coil HDY is reduced in accordance with the increased driving signal, so the horizontal size is decreased.
Accordingly, when the frequency of horizontal sync signal is lower than about 45KHz, the amplitude of driving signal is determined by the resistance of resistor 208. Further, when the frequency of horizontal sync signal is higher than about 45KHz, the amplitude of driving signal is determined by the resistance of resistor 208 and 408. Therefore, the amplitude of driving signal when the frequency of horizontal sync signal is higher than 45KHz is increased more than that of driving signal when the frequency of horizontal sync signal is lower than 45KHz. Hence, the quantity of current which flows in the horizontal deflection coil and horizontal picture size become constant regardless of the frequency of horizontal sync signal.
By employing a horizontal deflection circuit for the multi-mode monitor according to an embodiment of the invention, the amplitude of driving signal is controlled in accordance with the frequency of horizontal sync signal, so the quantity of current which flows to the horizontal deflection coil and the horizontal picture size become constant. Therefore, whether the mode of monitor is changed, the horizontal picture size becomes constant, so the quality of picture can increase.
While an embodiment of the present invention has been particularly shown and described, it will be understood that various changes in form and details may be made without departing from the scope of the invention as defined by the appended claims. For instance, while the preferred embodiments of the present invention herein are described for a monitor, the present invention may be applied to every video signal processing system such as general VCRs.
Claims (7)
1. A horizontal deflection circuit for a video signal processing system comprising means for generating a driving signal, means for controlling the amplitude of the driving signal in accordance with the frequency of an externally supplied horizontal sync signal, and generating means for generating a horizontal deflection signal having a sawtooth waveform, wherein said generating means is controlled by said adjusted driving signal whereby the horizontal deflection signal is stabilised.
2. A horizontal deflection circuit as claimed in Claim 1, wherein said means for controlling the amplitude of the driving signal comprise means for determining a mode in accordance with the frequency of said externally supplied horizontal sync signal.
3. A horizontal deflection circuit for a multi-mode monitor having a horizontal deflection coil for deflecting an electron to horizontal direction and for determining a mode such as VGA (video graphic adaptor), SVGA (super VGA) in accordance with a frequency of horizontal sync signal, comprising:
an oscillating means for receiving an externally-supplied horizontal sync signal and for outputting an oscillating signal;
a horizontal driving means for amplifying said oscillating signal in accordance with an amplitude of said externally-supplied voltage source and for generating a driving signal;
a microprocessor for determining a mode in accordance with said externally-supplied horizontal sync signal and for outputting a control signal to control an amplitude of said driving signal in accordance with said determined mode;
a driving signal controlling means connected to an output terminal of microprocessor for determining said amplitude of driving signal in accordance with said control signal; and
a horizontal output means for switching on and off, generating a horizontal deflection signal of sawtooth waveform, and for supplying said generated horizontal deflection signal to said horizontal deflection coil.
4. A horizontal deflection circuit for a multi-mode monitor as claimed in Claim 3, wherein said microprocessor generates said control signal of a high level when said frequency of horizontal sync signal is higher than a reference frequency and for generating said control signal of a low level when said frequency of horizontal sync signal is lower than said reference frequency.
5. A horizontal deflection circuit for a multi-mode monitor as claimed in Claim 3, wherein said driving signal controlling means includes:
a first resistor and a second resistor connected in series for dividing said control signal and for outputting a dividing signal, wherein one end of said first resistor is connected to said output terminal of said microprocessor;
a first transistor connected to the other end of said first resistor for switching on and off in accordance with said dividing signal, wherein one end of said second resistor is connected between the other end of said first resistor and a base side of said first transistor, and the other end of said second resistor is connected to the ground;
a second transistor connected to a collector side of said first transistor for switching on and off in accordance with the switching state of said first transistor;
a third resistor connected between a collector side of said first transistor and a base side of said second transistor for controlling a quantity of current which flows to said first transistor;
a fourth resistor connected between an emitter side of said second transistor and said base side thereof for supplying said driving signal of said horizontal driving means and for switching said second transistor on and off; and
a fifth resistor connected between said collector side of said second transistor and an output terminal of said horizontal driving means for determining said amplitude of driving signal in accordance with the switching a state of said second transistor on and off.
6. A horizontal deflection circuit for a multi-mode monitor for detemining a mode such as VGA (video graphic adaptor), SVGA (super VGA) in accordance with a frequency of horizontal sync signal and having a horizontal deflection coil for deflecting an electron to horizontal direction comprising:
an oscillating means for oscillating an externally-supplied horizontal sync signal and outputting an oscillating signal;
a horizontal driving means for amplifying said oscillating signal in accordance with an amplitude of said externally-supplied voltage source and generating a driving signal;
a microprocessor for determining a mode in accordance with said externally-supplied horizontal sync signal and outputting a control signal to control an amplitude of said driving signal in accordance with said determined mode;
a first resistor and a second resistor serially connected to said output terminal of microprocessor and grounded to an output terminal of said second resistor for dividing said control signal and outputting a dividing signal;
a driving signal controlling means connected to an output terminal of said microprocessor for determining an amplitude of said driving signal in accordance with said control signal, wherein said driving signal controlling means includes:
a first resistor and a second resistor connected in series for dividing said control signal and for outputting a dividing signal, wherein one end of said first resistor is connected to said output terminal of said microprocessor;
a first transistor connected to the other end of said first resistor for switching on and off in accordance with said dividing signal, wherein one end of said second resistor is connected between the other end of said first resistor and a base side of said first transistor, and the other end of said second resistor is connected to the ground;
a second transistor connected to a collector side of said first transistor for switching in accordance with the switching state of said first transistor;
a third resistor connected between a collector side of said first transistor and a base side of said second transistor for controlling a quantity of current which flows to said first transistor;
a fourth resistor connected between an emitter side of said second transistor and said base side thereof for supplying said driving signal of said horizontal driving means and for switching said second transistor; and
a fifth transistor connected between said collector side of said second transistor and an output terminal of said horizontal driving means for determining said amplitude of driving signal in accordance with the switching state of said second transistor; and
a horizontal output means for switching and generating a horizontal deflection signal of sawtooth waveform and for supplied said generated horizontal deflection signal to said horizontal deflection coil.
7. A horizontal deflection circuit substantially as hereinbefore described with reference to Figure 3 of the accompanying drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019970029774A KR19990005562A (en) | 1997-06-30 | 1997-06-30 | Horizontal Deflection Compensation Circuit for Multi-Mode Monitors |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB9809955D0 GB9809955D0 (en) | 1998-07-08 |
| GB2327025A true GB2327025A (en) | 1999-01-06 |
Family
ID=19512714
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9809955A Withdrawn GB2327025A (en) | 1997-06-30 | 1998-05-08 | Scan-frequency-dependent drive signal amplitude in a horizontal deflection circuit for a multi-mode monitor |
Country Status (2)
| Country | Link |
|---|---|
| KR (1) | KR19990005562A (en) |
| GB (1) | GB2327025A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2344983A (en) * | 1998-12-18 | 2000-06-21 | Daewoo Electronics Co Ltd | Horizontal output circuit |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2142200A (en) * | 1983-06-09 | 1985-01-09 | Rca Corp | Drive circuit for multiple scan rate line deflection circuit |
| GB2198901A (en) * | 1986-12-19 | 1988-06-22 | Philips Electronic Associated | Circuit arrangement with a high voltage bipolar transistor |
-
1997
- 1997-06-30 KR KR1019970029774A patent/KR19990005562A/en not_active Application Discontinuation
-
1998
- 1998-05-08 GB GB9809955A patent/GB2327025A/en not_active Withdrawn
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2142200A (en) * | 1983-06-09 | 1985-01-09 | Rca Corp | Drive circuit for multiple scan rate line deflection circuit |
| GB2198901A (en) * | 1986-12-19 | 1988-06-22 | Philips Electronic Associated | Circuit arrangement with a high voltage bipolar transistor |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2344983A (en) * | 1998-12-18 | 2000-06-21 | Daewoo Electronics Co Ltd | Horizontal output circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| KR19990005562A (en) | 1999-01-25 |
| GB9809955D0 (en) | 1998-07-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6020694A (en) | Horizontal size regulation circuit of display device | |
| JP3226876B2 (en) | Video display | |
| US6091213A (en) | Horizontal deflection circuit for a monitor | |
| GB2327025A (en) | Scan-frequency-dependent drive signal amplitude in a horizontal deflection circuit for a multi-mode monitor | |
| US6259217B1 (en) | Wide band horizontal size regulation circuit of a display | |
| KR19990003850A (en) | Center adjustment circuit of horizontal raster for monitor | |
| KR100221339B1 (en) | Horizontal deflection drive circuit in multi-mode monitor | |
| KR200159449Y1 (en) | A circuit for protecting a horizontal-output-transistor in a multi-mode monitor | |
| US6160364A (en) | Circuit for limiting horizontal image size of display | |
| KR19980068222U (en) | Horizontal deflection device with screen size compensation | |
| KR200172693Y1 (en) | Horizontal position control circuit of raster | |
| KR200179723Y1 (en) | Horizon stabilizing circuit | |
| KR100212840B1 (en) | Apparatus for controlling a horizontal-size in a monitor | |
| KR100226710B1 (en) | Horizontal deflection circuit in a monitor | |
| KR19990034336A (en) | Horizontal Output Transistor Protection Circuit in Multi-Mode Monitors | |
| KR100575169B1 (en) | A horizontal deflection circuit in a multi-mode video display system | |
| KR19990055316A (en) | Centering circuit of horizontal raster in monitor | |
| US6664747B2 (en) | Dynamic focus regulation circuit of display apparatus | |
| KR200158594Y1 (en) | Image correction circuit of local distortion image using micom | |
| KR19990037258U (en) | Horizontal deflection circuit of display device | |
| JP3858815B2 (en) | Cathode ray tube equipment | |
| KR20000074850A (en) | Apparatus for variably changing a horizontal output voltage in accordance with changing of a screen size of a display system | |
| KR980010734A (en) | Voltage compensation circuit of horizontal drive transformer | |
| KR19990005572A (en) | Horizontal Deflection Linearity Correction Method for Multimode Monitors | |
| KR19990037259U (en) | Horizontal deflection circuit of display device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |