| 摘要 |
PROBLEM TO BE SOLVED: To provide an automatic cut-off circuit for keeping chromaticity of black level by each of R, B, and G signals. SOLUTION: In the automatic cut-off circuit of a color television receiver, a total sum current value which is the sum of the currents flowing in respective cathodes for red, blue, and green is inputted such that a voltage conversion value converted from the current value to a voltage is fed back, when the voltage converted value of a control pulse is a predetermined peak value or over, an automatic cut-off pulse control unit 32 which outputs a control signal for causing an automatic cut-off pulse generating unit to generated a control pulses, previously stores characteristic data of conversion coefficient for attenuating the voltage converted value while maintaining such that the amplitude of the control pulse will not exceed a predetermined peak value, selects a conversion coefficient corresponding to the voltage converted value which is fed back from the characteristic data for outputting, and attenuates the voltage converted value which is feedback in accordance with the conversion coefficient for outputting.
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