Abstract: Reference clock CMOS input buffer with self-calibration and improved ESD performance. In one embodiment, a reference clock input buffer of an image sensor includes a Schmitt trigger configured to generate a clock signal having a falling edge and a rising edge. The falling edge and the rising edge are separated by a hysteresis voltage. The Schmitt trigger includes a plurality of output switches and a plurality of voltage control switches that are individually coupled to individual output switches [M2-i] of the plurality of output switches. Voltage of the falling edge signal or the rising edge signal of the Schmitt trigger is adjustable by selectively switching at least one voltage control switch of the plurality of voltage control switches.

Abstract: An inverter for converting an input direct current (DC) waveform from a DC source to an output alternating current (AC) waveform for delivery to an AC grid includes an input converter, an output converter, and an active filter, each of which is electrically coupled to a bus. The bus may be a DC bus or an AC bus. The input converter is configured to convert the input DC waveform to a DC or AC bus waveform. The output converter is configured to convert the bus waveform to the output AC waveform at a grid frequency. The active filter is configured to reduce a double-frequency ripple power of the bus waveform by supplying power to and absorbing power from the power bus.

Abstract: A voltage drive circuit is constructed by stacking NMOS and PMOS transistors to provide high voltage levels with an output voltage swing greater than the breakdown voltage of the individual transistors used to build the voltage drive circuit. The voltage drive circuit may include a series stack of capacitors connected between gates of the stacked PMOS and NMOS transistors. The capacitive loading causes the gate signals to change more synchronously. Errors in timing for these gate signals, which would otherwise result in damage from exceeding the breakdown voltage across a pair of terminals of one of the NMOS and PMOS transistors, are mollified.

Abstract: An apparatus and method for an electron beam manipulation coil for an x-ray generation system includes the use of a control circuit. The control circuit includes a first low voltage source, a second low voltage source, and a first switching device coupled in series with the first low voltage source and configured to create a first current path with the first low voltage source when in a closed position. The control circuit also includes a second switching device coupled in series with the second low voltage source and configured to create a second current path with the second low voltage source when in a closed position and a capacitor coupled in parallel with an electron beam manipulation coil and positioned along the first and second current paths.

Abstract: A cathode ray tube display apparatus having a fly back transformer (FBT) to induce and output high voltage, the CRT apparatus including: a power controller controlling source power input into the FBT; a DC power detector to output a shut-off signal to shut off an operation of the power controller if the DC power detector is supplied with a direct current signal. The CRT display apparatus provides for normal operation of a system while protecting circuit components from abnormal operation of the system.

Abstract: A display apparatus having a high voltage FBT driving circuit includes a transformer having a primary and a secondary coil, a high voltage detector to detect an output voltage of the secondary coil, a high voltage compensator to output a high voltage compensating signal based on the detected voltage, a DC voltage controller to adjust a DC voltage according to the high voltage compensating signal and to output the adjusted DC voltage to the primary coil, a horizontal deflector to generate a horizontal deflecting pulse based on the DC voltage, a turns ratio adjuster to adjust a turns ratio of the primary and secondary coils, and a controller to control the turns ratio adjuster so as to make the output DC voltage higher than a lower limit when the frequency of a received horizontal synchronous signal is lower than a predetermined reference level.

Abstract: A resonant pulse voltage having a positive polarity is applied by a first resonant circuit and a third resonant circuit to a horizontal deflection coil included in the first resonant circuit, and a resonant pulse voltage having a negative polarity which is opposite to that of resonant pulse voltages applied by the first resonant circuit and the third resonant circuit is applied to only a horizontal deflection coil in the first resonant circuit without being applied to a transistor by a second resonant circuit.

Abstract: The invention concerns a scanning circuit, comprising a power supply providing a negative voltage on a first terminal (Tdown), an intermediate voltage on a second terminal (Gnd) and a positive voltage on a terminal of a switch (S), the other terminal of the switch being connected to a third terminal (Tup), a control circuit (6) supplied by connections to the second and third terminals, a differential amplifier receiving a positive and a negative input signal provided by the control circuit, a power amplifier controlled by the differential amplifier, both amplifiers being supplied by connections to the first and third terminals, a deflection coil (Ly) connected between the output of the power amplifier and the second terminal, biasing means setting, when the switch is open, the output of the differential amplifier so that the possible current paths through the power amplifier between the deflection coil and the first terminal are cut.

Abstract: A display system capable of raising limits on the response speed of the spatial light modulator and the rate of pulse-width modulation signal transfer is provided at a low cost. The display system comprises: a color switch filter unit used in the sequential color separation of white light from the light source; a spatial light modulator which is illuminated by lights of plural color elements from the color switch filter unit and generates image lights of the respective color elements; and an intensity switch filter unit for switching three or more intensity levels of the respective lights of plural color elements, being separate from the color switch filter unit.

Abstract: Disclosed is a power-supplying apparatus for an electron gun in a color display tube (CDT) provided with an fly back transformer (FBT) having a focus voltage output terminal and an acceleration voltage output terminal, further having a power supplying part supplying a predetermined reference voltage; a focus voltage detection part detecting a focus voltage of the focus voltage output terminal; and a focus voltage boost part boosting the focus voltage of the focus voltage output terminal in case that the focus voltage detected by the focus voltage detection part is lower than the reference voltage of the power supplying part. With this configuration, it is possible to recover the voltage of the focus voltage output terminal dropped according to the grid discharging of the electron gun in the color display tube to the normal voltage.

Abstract: An image display is operable with video signals having a plurality of scanning frequencies and comprises a cathode ray tube for the display of ones of the video signals. A deflection coil is mounted on the cathode ray tube and a horizontal deflection amplifier is coupled to the deflection coil and generates a deflection current therein. A plurality of retrace capacitors are controllably coupled to the horizontal deflection amplifier in response to a selected scanning frequency to maintain a substantially constant active picture display area with the ones of the video signals having the plurality of scanning frequencies.

Abstract: A power supply for a video display tube includes a deflection transformer with a primary winding powered with a scan voltage which has a first value when displaying signal according to a first video standard and a second voltage when displaying video according to a second standard. A secondary winding of the transformer produces filament voltage for the display tube. A variable coupler couples the filament voltage to the filament of the picture tube in an amount established by a control signal. A memory produces a first control signal in response to the first scan voltage and a second control signal in response to the second scan voltage. The first and second control signals are selected so that the voltage coupled from the transformer to the filament is the same at both scan voltages.

Abstract: An electromagnetic quadrupole circuit capable of always performing the optimal correction of the spot form is provided with: a current detecting section 20 for detecting the peak value and bottom value of current flowing along an electromagnetic quadrupole coil 8; a control section 50 for supplying a prescribed peak control value and a prescribed bottom control value; a first power source 16 for controlling the feedback of the amount of supply current based on the peak value detected by the current detecting section 20 and the peak control value supplied from the control section 50; and a second power source 17 for controlling the feedback of the amount of supply current based on the bottom value detected by the current detecting section 20 and the bottom control value supplied from the control section 50.

Abstract: A horizontal deflection circuit output stage includes a trace capacitor for developing a trace voltage. A retrace capacitance is coupled to a deflection winding to form a retrace resonant circuit with the deflection winding, during a retrace interval of a deflection cycle. A rectifier for rectifying a retrace pulse voltage developed in the retrace capacitance. A switching transistor is coupled to the inductance and to the trace capacitor for applying the rectified retrace pulse voltage to the inductance to generate a current in the inductance. The inductance current is coupled to the trace capacitor, during the trace interval, to provide for linearity correction. The rectifier is coupled to the switching transistor for producing a rectified control signal at a control terminal of the switching transistor to cause a change of state in the switching transistor, during the retrace interval.

Abstract: The invention relates to a power supply (9) for a deflection circuit (1), that comprises a deflection coil (2) for connection to a picture tube, a drive circuit (4,5,6) connected to the deflection coil (2), and a deflection controller (3) for controlling the drive circuit (4,5,6). According to the invention the power supply (9) comprises a first input (10,11) connection to an output of the drive circuit (4,5,6) and the deflection coil, a second input connected to a power source (Vinput), a power supply output (13) connected to the drive circuit (4,5,6), and an adapter for adapting the power supply (VP) to the output (13) from the second input (Vinput) dependent on the first input (10,11).

Abstract: A display system capable of raising limits on the response speed of the spatial light modulator and the rate of pulse-width modulation signal transfer is provided at a low cost. The display system comprises: a color switch filter unit used in the sequential color separation of white light from the light source; a spatial light modulator which is illuminated by lights of plural color elements from the color switch filter unit and generates image lights of the respective color elements; and an intensity switch filter unit for switching three or more intensity levels of the respective lights of plural color elements, being separate from the color switch filter unit.

Abstract: A horizontal deflection circuit includes a horizontal deflection winding coupled to a retrace capacitor to form a retrace resonant circuit. An S-shaping capacitor is coupled to the deflection winding to form a first trace resonant circuit. A first switching transistor is responsive to a synchronizing first signal at a frequency related to a horizontal deflection frequency and coupled to the deflection winding for generating a deflection current in the deflection winding. A second switching transistor is responsive to the first signal and having first and second switching state, during first and second portions of the trace interval. The second switching transistor couples the S-shaping capacitor to a modulation inductance and to a modulation capacitor to form a second trace resonant circuit, during the second portion of the trace interval. The length of the second portion is modulated at a vertical rate parabolic manner for modulating a current in the S-shaping capacitor to provide modulated S correction.

Abstract: A method and device are described for detecting whether a flash (F) has occurred in the high voltage part of a combined high voltage and horizontal deflection circuit (100) in an apparatus comprising a cathode ray tube (CRT), such as for instance a television set, a monitor, etc. The possible flash is detected by checking the fly-back pulse (70) of the horizontal deflection circuit (16) for deviations that reflect the occurrence of a flash. One possible distortion indicative for the occurrence of a flash is bouncing of the fly-back pulse. Another possible distortion indicative for the occurrence of a flash is collapse of the fly-back pulse. Another possible deviation indicative for the occurrence of a flash is a substantial decrease of the storage time (&tgr;S) of the line deflection transistor (30).

Abstract: An apparatus for the correction of East-West distortion of images produced on the screen of a picture tube. More particularly, it concerns an electronic circuit for dynamically controlling the AC component of the drive signal to an East-West amplifier (14) in a picture tube horizontal scanning system. The electronic circuit comprises an input (44,66) for receiving a signal related to the beam current of the tube, an output for connection to the input of the East-West amplifier, a capacitive element (32,64), and an active control device (30,60) for controlling the capacitive element in response to the signal at the circuit input.

Abstract: A horizontal deflection circuit includes a first retrace capacitance and a second retrace capacitance. A horizontal deflection winding is coupled to the first and second retrace capacitances to form a resonant circuit, during retrace. A first switching transistor responsive to a first control signal at a horizontal deflection frequency selected from a range of horizontal deflection frequencies and coupled to the first retrace capacitance generates a first retrace pulse voltage in the first retrace capacitance. A second switching transistor responsive to a second control signal is coupled to the second retrace capacitance. A second retrace pulse voltage is generated in the second retrace capacitance. The second retrace pulse voltage is combined with the first retrace pulse voltage to produce a deflection current in the deflection winding.

Abstract: A horizontal deflection circuit of a video display includes a first retrace capacitance and a second retrace capacitance. A deflection winding is coupled to the first and second retrace capacitances to form a resonant circuit, during retrace. A first switching transistor is coupled to the first retrace capacitance for generating a resonant, first retrace pulse voltage in the resonant circuit. In a first embodiment of the invention, a second switching transistor is responsive to the first retrace pulse voltage and coupled to the second retrace capacitance for controlling the second switching transistor in accordance with the first retrace pulse voltage. A second retrace pulse voltage is generated in the second retrace capacitance in a manner to provide for capacitance transformation.

Abstract: A primary winding of a transformer is serially connected to a horizontal deflection coil. An amplitude regulating circuit outputs a first correction voltage in response to a voltage generated on a secondary winding of the transformer. A phase regulating circuit regulates the phase of the first correction voltage output from the amplitude regulating circuit and outputs a second correction voltage. An addition circuit adds the second correction voltage to a sawtooth wave voltage generated by a sawtooth wave voltage generation circuit. A correction current output from an amplifier in response to the second correction voltage output from the phase regulating circuit cancels a current component generated on a vertical deflection coil by a horizontal deflection current.

Abstract: In a horizontal deflection circuit, a waveform response of a horizontal output pulse must be adequately taken into account before and after a switching of the horizontal output pulse so that the waveform does not lack in shape and does not lose continuity at the switching. A switching apparatus for a horizontal driving apparatus includes (a) a horizontal driving pulse generator which generates a horizontal driving pulse from a horizontal synchronization signal, (b) an alternative signal generator which outputs an alternative signal different from the horizontal driving pulse, (c) a horizontal output control device which determines a timing to switch between the horizontal driving pulse and the alternative signal, and (d) a switching device which switches an output pulse with a control signal which is output from the horizontal output control device.

Abstract: A CRT driving voltage generating apparatus which can be realized and integrated at low cost, and can prevent breakdown and malfunction of circuits by actively adapting to a change in the frequency of a horizontal synchronous signal, and a CRT driving voltage generating method performed by the apparatus are provided. In this apparatus, a first comparator compares a reference value with the peak value of a fly back pulse. A stability controller shifts the level of the result of the comparison using a current mirroring technique and outputs a compared signal having a shifted level. A second comparator compares the compared signal with a sensing signal to obtain a reset signal. A pulse width modulated signal generator outputs a pulse width modulated signal having a level which is determined in response to the logic levels of a clock signal and a reset signal. A driving voltage generator generates the CRT driving voltage in response to the pulse width modulated signal.

Abstract: A monitor deflection circuit includes a bipolar power transistor for applying power from a high voltage supply to a horizontal deflection coil. The monitor deflection circuit further includes a base drive circuit for selectively turning the bipolar power transistor on and off. The base drive circuit includes a flyback transformer having a primary winding and a secondary winding coupled to the base of the bipolar power transistor, a voltage source coupled to one end of the primary winding, and a drive switch coupling the other end of the primary winding to ground. The base driver circuit further includes a constant current circuit coupled between the voltage source and the primary winding of the flyback transformer for controlling a base current of the bipolar power transistor before the bipolar power transistor conducts.

Abstract: A circuit for regulating an anode voltage in an information display apparatus. A horizontal deflection circuit has trace and retrace modes of operation. The horizontal deflection circuit further has a fixed retrace capacitance; and a series combination of a switched retrace capacitance and a switch element, which combination is coupled in parallel with the fixed retrace capacitance. The switch element is in a closed position as the horizontal deflection circuit enters the retrace mode of operation. A voltage divider network samples the anode voltage. A control circuit is responsive to the sample voltage for controlling the switch element, such that the control circuit effects regulation of the anode voltage by selecting a time during the retrace period at which to place the switch element in an open position. The control circuit may also provide a raster width compensation voltage for an east-west pincushion correction circuit.

Abstract: An image distortion correction circuit is provided in which a horizontal deflection current (IH) flows through horizontal correction coils (L1, L2) and a vertical deflection current (IV) flows through either of vertical correction coils (L3, L4). The vertical correction coils (L3, L4) and the horizontal correction coils (L1, L2) are wound on the same core (4). A pair of magnets (2, 3) on opposite ends of the core (4) apply a biased magnetic field from the north pole toward the south pole. The anode of a diode (D1), the cathode of a diode (D2) and a first end of a resistor (R1) are connected to an intermediate terminal (P11) through which the vertical deflection current (IV) flows. A first end of the vertical correction coil (L3) is connected to the cathode of the diode (D1). A second end of the resistor (R1) and a terminal (P4) are connected to a second end of the vertical correction coil (L3).

Abstract: At the onset of ageing or in the further course of their service life, color picture tubes relatively frequently exhibit a rise in the field strength between the cathode (K) and the Wehnelt electrode (G1) of the respective beam system on account of a blooming effect of the cathodes (K) which is known per se and reduces the spacing between cathode (K) and Wehnelt electrode (G1). The cut-off regulation reacts to an effect of this type in a manner such that the reverse voltage acting between cathode (K) and Wehnelt electrode (G1) is correspondingly reduced in order to be able to drive the same reference cathode current. However, the reaction of the cut-off regulation must be taken into account for the circuit design since this would otherwise result in an unacceptable reduction in the modulation range, which would, in turn, have an adverse effect on the maximum contrast setting.

Abstract: A horizontal position adjusting circuit for a raster includes a reference voltage outputting unit for outputting a reference voltage to enable a raster to be centered on a fluorescent screen; a reference voltage adjusting unit for varying an output voltage of the reference voltage outputting unit in accordance with an operating mode for displaying an image signal; and a deflection voltage outputting unit for generating a deflection voltage in accordance with the output signal of the reference voltage outputting unit, and for applying it to a horizontal deflection coil. In accordance with the present invention, the position of the raster formed on the fluorescent screen of the cathode-ray tube is automatically adjusted according to the operating mode so that positioning of the image screen on the fluorescent screen is simply adjusted to be at the center of the fluorescent screen, resulting in improved reliability of the display device.

Abstract: A resistor-capacitor-diode clamp is coupled to an S-capacitance of a horizontal deflection circuit output stage for reducing ringing by causing critical damping. The supply voltage of the output stage varies at a vertical rate parabolic manner for modulating the horizontal deflection current to provide East-West correction. A clamp capacitor of the clamp has a terminal that is direct current coupled to the supply voltage. Therefore, each terminal of the clamp capacitor has the same vertical rate parabola component. Consequently, the DC voltage difference developed between the terminals of the clamp capacitor does not include any vertical rate parabola component, the result is that the sensitivity of the damping to the supply voltage vertical rate variations is, advantageously, eliminated or reduced.

Abstract: A power source to drive a deflecting output unit is fixed, thereby simplifying so that it is possible to cope with two or more different horizontal frequencies. A resonance capacitor 4a and an auxiliary resonance capacitor 4b are serially connected and a variable capacitive switching element 7 to short-circuit the capacitor 4b is connected. When a tracing period changes from Tt to Tt′ (Tt<Tt′) in correspondence to a change from a first horizontal frequency on the high side to a second horizontal frequency on the low side, by turning on the variable capacitive switching element 7, the capacitor 4b is short-circuited and a capacitance is increased from C1•C1′/(C1+C1′) to C1, thereby enabling (Tr′=Tr•Tt′/Tt) to be satisfied. Even when a fixed power source is used, a voltage of a retrace pulse does not change and a fluctuation of another voltage such as an anode voltage or the like which is formed from the retrace pulse can be prevented.

Abstract: A deflection circuit includes a deflection correction circuit (Vs) with a controllable active voltage source (Vs) arranged in a loop formed by a deflection coil (Ld), an S-capacitor (Cs), and a flyback capacitor (Cf). The voltage source (Vs) receives a further power supply voltage (Vb2) and a modulating signal (M) to supply a modulating voltage (Vm) varying in response to the modulating signal (M). The active voltage source (Vs) includes a switching element (S2) which is switched on and off with a frequency which is substantially higher than the deflection frequency to to enable waveforms of the modulating voltage (Vm) with a frequency content which is substantially higher than the deflection frequency such that any desired waveform can be generated within the deflection period (Td).

Abstract: In a horizontal deflection circuit output stage of a video display monitor capable of operating at multi-scan rates, a given S-capacitor, selected from a bank of S-capacitors, provide S-correction at a corresponding range of frequencies. A resistor-capacitor-diode clamp selected from a bank of clamps is coupled to the selected S-capacitor for reducing ringing by causing critical damping. The in-circuit selected resistor-capacitor-diode clamp is selectable, in accordance with the selected horizontal deflection frequency.

Abstract: A circuit fixedly limits the horizontal image size of a screen of a CRT display. The circuit for limiting the horizontal image size of the screen detects a voltage indicative of the horizontal image size of the screen with power provided to a horizontal output unit by a field effect transistor in a horizontal output power supply unit. A current mirror circuit coupled to the field effect transistors outputs current which flows into the drain of a field effect transistor when the field effect transistor is turned on. The outputted current is transformed into voltage and the voltage is fed back to the PWM control circuit to limit the horizontal image size of the screen.

Abstract: A compensation control circuit of horizontal scanning size suitable to be used in a general monitor to compensate the variation amount of horizontal scanning size due to the influence of the anode load current. The compensation control circuit includes two parts: One is the horizontal scanning size compensation circuit and the other is the horizontal scanning size control circuit. The horizontal scanning size compensation circuit is coupled to the coil of the fly-back transformer to generate a corresponding compensation signal according to the variation of the anode load current. The compensation signal is far lower than the level of the anode voltage. Therefore, it can be processed by the general electric circuits. The horizontal scanning size control circuit is coupled to the horizontal scanning size compensation circuit to receive the compensation signal. The compensation signal can combine with the shift regulation signal sent by the microprocessor to be a D.C. modulation signal. Then the D.C.

Abstract: The present invention is a method and apparatus for selecting a capacitor value corresponding to a horizontal frequency in a video monitor. The technique determines the horizontal frequency and creates a limit on a default capacitor value which is obtained from the determined horizontal frequency. An updated value is compared with the limit to generate a comparison result. The capacitor value between the default capacitor value and the updated value is selected based on the comparison result.

Abstract: A horizontal deflection circuit is provided in which a large retrace pulse voltage applied to a horizontal deflection yoke can be taken to reduce the deflection current and which is capable of easily performing horizontal image size adjustment and distortion adjustment. A parallel connection of a switching element, a damper diode, and a resonance capacitor is connected in series to a parallel connection of another switching element, another damper diode, and another resonance capacitor, and power is supplied from the connection point via a fly-back transformer. The comparison value of the retrace pulse voltages applied across both ends of the switching elements is fed back through a switching element control circuit to the switching element so that the deflection current of the horizontal deflection yoke is controlled.

Abstract: A video imaging apparatus includes a source of a periodic dynamic focus voltage blanking signal. A dynamic focus voltage amplifier includes a switch responsive to the dynamic focus voltage blanking signal for applying a dynamic focus voltage to a focus electrode, when the switch is at a first state, and for disabling the application of the dynamic focus voltage, when the switch is at a second state to provide for automatic kine bias measurement. A second switch responsive to the focus voltage blanking signal is coupled to the amplifier for applying a current to a stage of the amplifier, when the dynamic focus voltage is disabled. The applied current adjusts the focus voltage, to a level closer to that established immediately after the dynamic focus voltage is enabled for reducing a transient condition.

Abstract: A television apparatus set has the capability of selectively displaying picture information obtained from a broadcast television signal and a display monitor data signal. A zero voltage switching switch mode power supply generates a higher voltage B+ supply voltage for a horizontal deflection circuit output stage, when the deflection circuit output stage operates at a rate greater than or equal to approximately 32 KHz. A series-pass regulator power supply generates at a common supply terminal a lower voltage B+ supply voltage, when the deflection circuit output stage operates at a lower rate equal to approximately 16 KHz. During a start-up interval, the horizontal scanning output stage is supplied with the lower B+ supply voltage regardless of the scan frequency for reducing excessive stress in the horizontal output stage switching transistor to improve reliability.

Abstract: A scan frequency detector is responsive to a horizontal synchronization signal to generate a data signal that is indicative of the horizontal scan frequency. A digital-to-analog (D/A) converter produces from the data signal an analog, output signal at a first level, when the horizontal frequency is within a first range of values, at a second level, when the horizontal frequency is within a second range of values and at a third level, when the horizontal frequency is within a third range of values. A first switch of a switched S-capacitor arrangement, is turned on, when the output signal is at the first level. The first switch and a second switch of the switched S-capacitor arrangement, are turned on, when the output signal is at the second level. Both the first and second switches are turned off, when the output signal is at the third level. The third and second levels are distinguished by a level detector that includes a zener diode.

Abstract: A horizontal deflection drive circuit using a plurality of FETs is provided, which includes a base drive current supply for receiving an oscillation pulse in a low level generated by an oscillation element, to perform switching operation, a P-channel FET for receiving the oscillation pulse in a low level generated by the oscillation element, and receiving current from the base drive current supply, to perform switching operation, an N-channel FET for receiving an oscillation pulse in a high level generated by the oscillation element, to perform switching operation, and a drive transformer for inducing current supplied from a deflection current supply according to the switching operations of the P-channel FET and N-channel FET, the P-channel FET being switched by the current supplied from the base drive current supply.

Abstract: A diode modulator circuit which is adapted to supply an acceptable S-correction of the S-linearity error of the line scanning of a picture tube (CRT) at substantially different line scan widths. A known diode modulator has two loops. The first loop includes a series arrangement of a line deflection coil (LD) and an S-capacitor (CS), which series arrangement is arranged in parallel with a first flyback capacitor (CF1) and a first diode (D1). The second loop includes a modulator coil (LB) arranged in parallel with a second flyback capacitor (CF2) and a second diode (D2). The two loops are arranged in series. An inner-pincushion capacitor (CSM) is arranged in a common path in which the line deflection current (Id) and a modulator current (Ib) flowing through the modulator coil (LB) flow in opposite directions. The amount of S-correction depends on the values of the S-correction capacitor (SC) and the inner-pincushion capacitor (CSM). The S-capacitor (CS) has been omitted in the subject diode modulator.

Abstract: A method and apparatus for testing the horizontal drive stage of a cathode ray tube display where the horizontal drive stage has a drive output which is directed to the base of a horizontal output transistor. In the method and apparatus, the output from the horizontal drive circuit is disconnected from the base of the horizontal output transistor and is connected to the apparatus of the present invention. The apparatus includes a load which simulates the load normally provided by the base of the horizontal output transistor. A meter differential amplifier is connected across the load and readings therefrom are projected on a display. The horizontal drive stage is then energized and readings from the display are compared to known operating requirements of the base of the horizontal output transistor.

Abstract: A horizontal deflection circuit including a horizontal deflection output circuit and a horizontal sawtooth wave current generation circuit. The horizontal output deflection circuit has a horizontal deflection coil and an S-shape capacitor connected in series with the horizontal deflector coil for supplying a horizontal deflection current to the horizontal deflector coil and the S-shape capacitor in accordance with a horizontal drive pulse.

Abstract: The invention relates to a dynamic focusing circuit with an output (1) for supplying a dynamic focusing voltage (Vf) to a focus electrode of a cathode ray tube (CRT). The dynamic focusing voltage (Vf) has, in succession, a falling edge, an almost flat part and a rising edge. A first transistor (T1) has a main current path (c1, e1) coupled between a supply voltage (V+) and the output (1). An arrangement of a secondary winding (Ls) of a transformer (T) and a current determining circuit (12) is coupled between the control input (b1) of the first transistor (T1) and the output (1). The current determining circuit (12) supplies a bias current (Ib). A second transistor (T2) has a control electrode (b2) for receiving an input voltage (Vi) related to a parabolically shaped input waveform (Vin), and a main terminal (c2) coupled to the control input (b1) of the first transistor to withdraw current (Id) from the control input (b1).

Abstract: A wide band high voltage stabilizing circuit supplies optimum voltage to a fly back transformer (FBT) according to the change of horizontal frequency or high voltage by connecting a charge storage unit and switching element to a primary coil of the FBT, the switching element being turned on or off according to a switching signal which a microcomputer recognizing a horizontal sync frequency signal applies corresponding to a frequency band.

Abstract: A deflection circuit generates a deflection current (If) through a deflection coil (Lf). The deflection circuit includes a series resistor (Rs) arranged in series with the deflection coil (Lf) to supply a feedback voltage (Vf;Vr), and a drive circuit (1,5) which has an output coupled to the series arrangement of the deflection coil (Lf) and the series resistor (Rs). The drive circuit (1,5) has an input coupled to the series resistor (Rs) to receive a feedback voltage (Vs). The drive circuit (1,5) further is coupled to a conversion resistor (Rc) for receiving an input waveform (Vi). The drive circuit (1,5) is arranged in a feedback loop to obtain a deflection current (If) with a shape resembling the input waveform (Vi). The deflection circuit further includes a damping impedance (Rd) arranged in parallel with the deflection coil (Lf), and a current generating circuit (3) for generating a correction current (Ic) within the flyback period (Tf).

Abstract: The present invention relates to a proximity detecting device for detecting the presence of an object in a target area, comprising a low voltage power source, a circuitry for generating electrical pulses and supplying them to a light emitting diode (LED) in order to emit light pulses, and a receiver for reception of light pulses emitted from the LED and directed towards said target area, characterised in that said circuitry comprises a first circuitry containing a primary coil and switching means for connecting the primary coil for a period of time to said low voltage power source such as to accumulate a predetermined amount of magnetic energy in the primary coil, and a second circuitry containing said LED and a secondary coil magnetically coupled to said primary coil to transform the accumulated magnetic energy by mutual induction upon opening said switching means each time into one of said electrical pulses.

Abstract: The turn-off period of the FET (111) is adjusted by changing the output pulse width of the MM (113) according to the horizontal deflection frequency, to adjust the total capacitance value of the S-shape correcting capacitor group in one horizontal deflection period, that is, to execute an optimum S-shape distortion correction according to each horizontal deflection frequency. The timing at which the electronic switch element (111) is turned off in a first half of the horizontal scanning period is continuously and variably controlled on the basis of an external control signal (Vg). The auxiliary S-shape correcting capacitor (110) of the S-shape correcting capacitor group is controllably turned on or off by the electronic switch element (111), to execute an optimum S-shape distortion correction.

Abstract: A horizontal deflection output circuit has a resonance circuit including a horizontal deflection yoke for generating the horizontal deflection signal, a first switch element, a second switch element comprising a bipolar transistor, and a circuit for applying a reverse bias voltage to the emitter-base junction of the bipolar transistor during a retrace period to remove excess minority carriers stored in its base rapidly, thereby making high speed switching operation of the transistor possible.