Video Processor with Automatic Cut-off Control using TDA4686

Video Processor TDA4686

Video Processor with Automatic Cut-off Control using TDA4686

Video Processor with Automatic Cut-off Control using TDA4686

General Description
The TDA4686 is a monolithic integrated circuit with a luminance and a colour difference interface for video processing in TV receivers. Its primary functions 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 a feature module.

Features
Intended for double line frequency application (100/120Hz).
Operates from an 8V DC supply.
Black level clamoing 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 RGB inputs.
Saturation, contrast, brightness and white adjusment 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 sychronization and cut-off timing pulses.
Automatic cut-off control or clamped output selectable via I2C-bus.
Automatic cut-off control with picture tube leakage current compensation.
Cut-off measurement pulses after end of the vertical blanking pulse or end of an extra vertical flyback pulse.
Increased RGB signal bandwidths.
Two switch-on delays to prevent discolouration before steady-state operation.
AVerage beam current and peak drive limiting.
PAL/SECAM or NTSC matrix selection via I2C-bus.
Emitter-folowwer RGB output stages to drive the video output stages.
I2C-bus contolled DC output e.g. for hue-adjust of NTSC (multistandard)decoders.
No daly of clamoing pulse.
Large luminance, colour difference and RGB bandwidth.