Patent ID: 6087789
Filing Date: 2000-07-11
Classification: G09G,H04N

Abstract:
A circuit to cause current to flow in a deflection coil as a function of an input signal representing a desired current flowing through said deflection coil, said circuit comprising:a) a differential amplifier providing a signal representing the difference between said desired current and the actual current flowing through said deflection coil with said first differential amplifier output coupled to a first terminal of said deflection coil with one said differential amplifier input responsive to said input signal;b) current sense means providing a signal to said differential amplifier producing a signal representing the actual current flowing through said deflection coil;c) switch means for coupling to a second terminal of said deflection coil, one of a first voltage, a second voltage and a third voltage, wherein said first voltage has a positive potential, said second voltage has a potential substantially at ground and a third voltage has a negative potential;d) a first comparator coupled to said differential amplifier and a first trip threshold voltage value;e) a second comparator coupled to said differential amplifier and a second trip threshold voltage value;f) switch drive logic coupled to said first and second comparators and said switch means operable to select one of said three switch potentials responsive to output signals provided by said first and second comparators.