TDA4685 Overview
The TDA4685 is a monolithic integrated circuit with a luminance and a colour difference interface for video processing in TV receivers. Its primary function is to process the luminance and colour difference signals from a colour decoder which is equipped e.g. with the multistandard decoder TDA4655 or TDA9160 plus delay line TDA4661 and the Picture Signal Improvement (PSI) IC, TDA467X, or from.
TDA4685 Key Features
- Operates from an 8 V DC supply
- Black level clamping of the colour difference, luminance and RGB input signals with coupling-capacitor DC level storage
- Two analog RGB inputs, selected either by fast switch signals or via I2C-bus; brightness and contrast control of both RG
- Saturation, contrast, brightness and white adjustment via I2C-bus
- Same RGB output black levels for Y/CD and RGB input signals
- Timing pulse generation from either a 2 or 3-level sandcastle pulse for clamping, vertical synchronization and cut-off t
- Automatic cut-off control or clamped output selectable via I2C-bus
- Automatic cut-off control with picture tube leakage current pensation
- Cut-off measurement pulses after end of the vertical blanking pulse or end of an extra vertical flyback pulse
- Two switch-on delays to prevent discolouration before steady-state operation