Chroma control circuit for a digital television receiver

摘要: In a chroma control circuit for digital television receiver, the system clock lies in range of four-times chrominance-subcarrier frequency. The originally received color-burst signal is locked frequency and phase to by means an all-digital phase-locked loop. phase-difference angle between appears as sine or cosine value two standard color-difference signals chrominance demodulator during reception signal. One signals, B-Y signal, fed through horizontal-frequency-suppressing loop filter oscillator. latter determines speed rotation hue adjustment rotating at approximately constant angular speed. respective values are read data from first second read-only memories, respectively, inputs adjuster calculating stage which derives