The TDA3508 is an integrated circuit which performs video control functions in a PAL/SECAM decoder for negative colour difference signals −(R−Y) and −(B−Y).

• Capacitive coupling of the colour difference and
luminance input signals with black level clamping in the
input stages
• Linear saturation control acting on the colour difference
signals
• (G−Y) and RGB matrix
• Linear transmission of inserted signals
• Equal black levels for inserted and matrixed signals
• Three identical channels for the RGB signals
• Linear contrast and brightness controls, operating on
both the inserted and matrixed RGB signals
• Peak beam current limiting input
• Clamping, horizontal and vertical blanking of the three
input signals controlled by a 3-level sandcastle pulse
• Three DC gain controls for the RGB output signals
(white point adjustment)
• Emitter-follower outputs for driving the RGB output
stages
• Input for automatic cut-off control with compensation for
leakage current of the picture tube