| 摘要 |
The CRT beam current control circuit detects the voltage generated by a high voltage generating circuit and controls the beam current by controlling the voltage applied to the CRT and a control grid. The circuit includes a control voltage generator (18) for driving the voltage applied to the CRT (10) and input power (VCC1) according to the control signals, a negative voltage rectifier connected between secondary winding of a flyback transformer and the control voltage generator (18) for applying voltage to a control grid (G1) of the CRT (10), a comparator (22) for generating reference voltage (V1-Vzp) and for overlapping the reference voltage over the start point voltage (Z) of the secondary winding, a first controller (24) for comparing the output voltage of the comparator to reference voltage (V2) to generate a first control signal, and a second controller (26) for generating a second control signal using a second reference voltage and the output voltage of the comparator.
|
