Blanking circuit for use in a display apparatus which has a cathode-ray tube Patent #: 4814880
ApplicationNo. 683058 filed on 04/10/1991
US Classes:315/381, Circuits control grid-cathode circuit of tube315/384Ray blanking
ExaminersPrimary: Issing, Gregory C.
Attorney, Agent or Firm
Foreign Patent References
International ClassesG09G 001/04
Foreign Application Priority Data1990-04-20 JP
AbstractA spot killer circuit for a cathode ray tube having blanking function is configured to be provided with a positive voltage source, a negative voltage source, two diodes, condensers and a resistor in order to perform blanking in horizontal scanning or vertical scanning by using a first grid of the cathode ray tube. In the configuration, the two diodes are inserted in series between the negative voltage source and the first grid, and a first condenser is inserted between a junction of the two diodes and the positive voltage source. A resistor is connected in parallel with the diode connected to the first grid, and a blanking signal is applied to the first grid through a second condenser.