Scanning circuit of electron tube displays
AssigneeSTMicroelectronics S.r.l.
InventorJean-Michel Moreau
Life of this patent
Estimating the term…
Abstract
The invention concerns a control circuit for an electron tube display comprising a deflection coil, the deflection coil being part of a scanning circuit and being coupled to a coil of a transformer powering a high voltage generator used to accelerate an electron beam, a phase locked loop being used to keep in phase the flyback pulses produced by the scanning circuit and the video signal synchronisation pulses, and comprising an electron beam current measuring circuit, a compensation circuit for compensating the phase difference between the flyback pulses and the video signal synchronisation pulses as a function of the measured current.
Claims19
A control circuit for an electron tube display comprising a deflection coil, the deflection coil being part of a scanning circuit and being coupled to a coil of a transformer powering a high voltage generator used to accelerate an electron beam, a phase locked loop being used to keep in phase the flyback pulses produced by the scanning circuit and the video signal synchronisation pulses, comprising:
- an electron beam current measuring circuit,
- a compensation circuit for compensating the phase difference between the flyback pulses and the video signal synchronisation pulses as a function of the measured current.
A control circuit for an electron tube display comprising a scanning circuit and a phase locked loope that is used to keep flyback pulses produced by the scanning circuit and video signal synchronization pulses in phase, the phase locked loop comprising an electron beam current measuring circuit, and a compensation circuit for compensating a phase difference between the flyback pulses and the video signal synchronization pulses in response to a measured current.
A display control circuit, comprising:
- a circuit that measures an electron beam current;
- and
- a compensation circuit that compensates a phase difference between flyback pulses and video signal synchronization signals in response to at least the electron beam current;
- and
- a phase comparator that provides an output signal in response to at least the phase difference and the electron beam current.
A method of controlling a display, comprising:
- measuring an electron beam current;
- and
- compensating a phase difference between flyback pulses and video signal synchronization signals in response to at least the electron beam current;
- wherein the compensating comprises providing a control signal in response to at least the electron beam current;
- and
- wherein the compensating further comprises receiving the control signal and adjusting an output of a phase comparator in response to at least the control signal.
Dependencies are inferred from the claim text.