The TDA3505 and TDA3506 are monolithic integrated circuits that perform video control functions in a PAL/SECAM decoder. The TDA3505 is for negative color difference signals -(R-Y), -(B-Y), and the TDA3506 is for positive color difference signals +(R-Y), +(B-Y). The required input signals are luminance and color difference (negative or positive) and a 3-level sandcastle pulse for control purposes. Linear RGB signals can be inserted from an external source. RGB output signals are available for driving the video output stages. The circuits provide automatic cut-off control of the picture tube.
