TDA4687 Philips Semiconductors, TDA4687 Datasheet - Page 2

• Manufacturer Part Number: TDA4687
• Description: Video processor with automatic cut-off control
• Manufacturer: Philips Semiconductors

Philips Semiconductors
FEATURES
GENERAL DESCRIPTION
The TDA4687 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
ORDERING INFORMATION
1997 Jun 23
TDA4687
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 I
both RGB inputs
Saturation, contrast, brightness and white adjustment
via I
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 timing pulses
Automatic cut-off control or clamped output selectable
via I
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
Ultra-black or nominal black blanking selectable via
I
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 I
Emitter-follower RGB output stages to drive the video
output stages
I
NTSC (multistandard) decoders
Positive amplification factor of cut-off control voltage.
TYPE NUMBER
Video processor with automatic cut-off control
2
2
C-bus in clamped output mode
C-bus controlled DC output e.g. for hue-adjust of
2
2
C-bus
C-bus
2
C-bus; brightness and contrast control of
NAME
DIP28
plastic dual in-line package; 28 leads (600 mil)
2
C-bus
2
line TDA4661 and the Picture Signal Improvement (PSI)
IC, TDA467X, or from a feature module.
The required input signals are:
Two sets of analog RGB colour signals can also be
inserted, e.g. one from a peritelevision connector and the
other from an on-screen display generator. The TDA4687
includes full I
functions with automatic cut-off control of the picture tube
cathode currents. It provides RGB output signals for the
video output stages.
The TDA4687 is a simplified, pin compatible (except for
pin 18) version of the TDA4680. The module address via
I
included in the TDA4687 the I
executed. The differences with the TDA4680 are:
The TDA4686 is like TDA4687 but intended for double line
frequency application.
2
DESCRIPTION
C-bus can be used for both ICs; where a function is not
Luminance and negative colour difference signals
2 or 3-level sandcastle pulse for internal timing pulse
generation
I
control.
No automatic white level control; the white levels are
determined directly by the I
RGB reference levels for automatic cut-off control are
not adjustable via I
Clamping delay is fixed
Only contrast and brightness adjust for the RGB input
signals
The measurement lines are triggered either by the
trailing edge of the vertical component of the sandcastle
pulse or by the trailing edge of an optional external
vertical flyback pulse (on pin 18), according to which
occurs first.
2
PACKAGE
C-bus data and clock signals for microcontroller
2
C-bus control of all parameters and
2
C-bus
2
2
C-bus data
C-bus command is not
Product specification
TDA4687
VERSION
SOT117-1