Horizontal Deflection Signal Processing/Vertical And Geometrical Compensation Of The Raster - NEC MultiSync 75F-3 Service Manual

3. Horizontal deflection signal processing / Vertical and geometrical compensation of the raster
I²C-bus autosync deflection controller for PC monitors
FEATURES
Concept features
§ Full horizotal plus vertical autosync capability
§ Extended horizontal frequency range from 15 to
130kHz
§ Comprehensive set of I²C-bus driven geometry
adjustments and functions, including standby
mode
§ Very good vertical linearity
§ Moire cancellation
§ Start-up and switch-off sequence for safe opera-
tion of all power components
§ X-ray protection
§ Power dip recognition
§ Flexible switched mode B+ supply function block
for feedback and feed forward converter
§ Internally stabilized voltage reference
§ Drive signal for focus amplifiers with combined
horizontal and vertical parabola waveforms
§ DC controllable inputs for Extremely High Ten-
sion (EHT) Compensation
§ SDIP32 Package
Synchronization
§ Can handle all sync signals (horizontal, vertical,
composite and sync-on-video)
§ Output for video clamping (leading/trailing edge
selectable by the I²C-bus), vertical blanking and
protection blanking
§ Output for fast unlock status of horizontal syn-
chronization and blanking on grid 1 of picture
tube.
Horizontal section
§ I²C-bus controllable wide range linear picture
position, pin unbalance and parallelogram
correction via horizontal phase
§ Frequency-locked loop for smooth catching of
horizontal frequency
§ Simple frequency preset of fmin and fmax by
external resistors
§ Low jitter
§ Soft start for horizontal and B+ control drive
signals.
Vertical section
§ I²C-bus controllable vertical picture size, picture
position, linearity (S-correction) and linearity
balance
§ Output for the I²C-bus controllable vertical
sawtooth and parabola (for pin unbalance and
parallelogram)
§ Vertical picture size independent of frequency
§ Differential current outputs for DC coupling to
vertical booster
§ 50 to 160 Hz vertical autosync range.
East-West (EW) section
§ I²C-bus controllable output for horizontal
pincushion, horizontal size, corner and trapezium
correction
§ Optional tracking of EW drive waveform with line
frequency selectable by the I²C-bus.
Focus section
§ I²C-bus controllable output for horizontal and
vertical parabolas
§ Vertical parabola is independent of frequency
and tracks with vertical adjustments
§ Horizontal parabola independent of frequency
§ Adjustable pre-correction of delay in focus output
stage.
57
TDA4857